Fix helm chart to generate correct NicClusterPolicy

[ykulazhenkov]

To be able to use server-side apply YAML spec
should not contain "null" values

Changes:

• quote strings without default to always include a empty string value
• use empty list for imagePullSecrets field if secrets are not configured

Fixes #452

Example of generated NicClusterPolicy

apiVersion: mellanox.com/v1alpha1                                                                                                                                                                                                                                                                                                [101/7155]
kind: NicClusterPolicy                                                                                                                                                                                        
metadata:                                                                                                                                                                                                     
  name: nic-cluster-policy                                                                                                                                                                                    
spec:                                                                                                                                                                                                         
  ofedDriver:                                                                                                                                                                                                 
    image: mofed                                                                                                                                                                                              
    repository: nvcr.io/nvidia/mellanox                                                                                                                                                                       
    version: 5.9-0.5.6.0                                                                                                                                                                                      
    imagePullSecrets: []                                                                                                                                                                                      
    terminationGracePeriodSeconds: 300                                                                                                                                                                        
    startupProbe:                                                                                                                                                                                             
      initialDelaySeconds: 60                                                                                                                                                                                 
      periodSeconds: 60                                                                                                                                                                                       
    livenessProbe:                              
      initialDelaySeconds: 30                   
      periodSeconds: 30                                                                                
    readinessProbe:                                                                                    
      initialDelaySeconds: 10                                                                          
      periodSeconds: 30
    upgradePolicy:                                                                                     
      autoUpgrade: false                  
      maxParallelUpgrades: 1
      drain:               
        enable: true                                                                                   
        force: false                   
        podSelector: ""                  
        timeoutSeconds: 300                                                                            
        deleteEmptyDir: false
  rdmaSharedDevicePlugin:               
    # [map[name:rdma_shared_device_a vendors:[15b3]]]                                                  
    image: k8s-rdma-shared-dev-plugin
    repository: nvcr.io/nvidia/cloud-native
    version: v1.3.2                                                                                                                                                                                           
    imagePullSecrets: []                                                                               
    # The config below directly propagates to k8s-rdma-shared-device-plugin configuration.
    # Replace 'devices' with your (RDMA capable) netdevice name.
    config: |
      {
        "configList": [
          {
            "resourceName": "rdma_shared_device_a", 
            "rdmaHcaMax": 1000,
            "selectors": {
              "vendors": ["15b3"],
              "deviceIDs": [],
              "drivers": [],
              "ifNames": [],
              "linkTypes": []                              
            }                                              
          }                                                
        ]                                                           
      }                                                             
  psp:                                                              
    enabled: false 

With imagePullSecrets

apiVersion: mellanox.com/v1alpha1               
kind: NicClusterPolicy                      
metadata:                                   
  name: nic-cluster-policy                                         
spec:                                 
  ofedDriver:                                      
    image: mofed
    repository: nvcr.io/nvidia/mellanox
    version: 5.9-0.5.6.0
    imagePullSecrets: ["foo","bar"]     
    terminationGracePeriodSeconds: 300
    startupProbe:                                  
      initialDelaySeconds: 60                   
      periodSeconds: 60                              
    livenessProbe:                               
      initialDelaySeconds: 30             
      periodSeconds: 30                                
    readinessProbe:                                
      initialDelaySeconds: 10                                   
      periodSeconds: 30                  
    upgradePolicy:                                                 
      autoUpgrade: false    
      maxParallelUpgrades: 1                                                
      drain:                           
        enable: true                            
        force: false  
        podSelector: ""
        timeoutSeconds: 300
        deleteEmptyDir: false                         
  rdmaSharedDevicePlugin:            
    # [map[name:rdma_shared_device_a vendors:[15b3]]]
    image: k8s-rdma-shared-dev-plugin                                                                                                                                
    repository: nvcr.io/nvidia/cloud-native
    version: v1.3.2
    imagePullSecrets: ["foo","bar"]
    # The config below directly propagates to k8s-rdma-shared-device-plugin configuration.
    # Replace 'devices' with your (RDMA capable) netdevice name.
    config: |
      {
        "configList": [
          {
            "resourceName": "rdma_shared_device_a",
            "rdmaHcaMax": 1000,
            "selectors": {
              "vendors": ["15b3"],
              "deviceIDs": [],
              "drivers": [],
              "ifNames": [],
              "linkTypes": []
            }
          }
        ]
      }
  psp:
    enabled: false

[rollandf]

LGTM