[BUG] sidecarset doesn't add volumes used by initContainers

[outgnaY]

What happened:
sidecarset doesn't add volumes used by initContainers, it will only add volumes used by sidecar containers instead, which cause
What you expected to happen:

How to reproduce it (as minimally and precisely as possible):
sidecarset.yaml

apiVersion: apps.kruise.io/v1alpha1
kind: SidecarSet
metadata:
  name: test-sidecarset
spec:
  selector:
    matchLabels:
      app: nginx
  updateStrategy:
    type: RollingUpdate
    maxUnavailable: 1
  initContainers:
  - name: init-container
    image: busybox:latest
    command: [ "/bin/sh", "-c", "sleep 10 && echo 'init container success'" ]
    volumeMounts:
    - name: log-volume
      mountPath: /var/log
  volumes: # this field will be merged into pod.spec.volumes
  - name: log-volume
    emptyDir: {}

pod.yaml

apiVersion: v1
kind: Pod
metadata:
  labels:
    app: nginx
  name: pod-1
spec:
  containers:
    - name: busybox
      image: busybox
      command:
        - sleep
        - "3600"

-> kubectl apply -f pod.yaml
The Pod "nginx" is invalid: spec.initContainers[0].volumeMounts[0].name: Not found: "log-volume"
Anything else we need to know?:

Environment:

• Kruise version:
• Kubernetes version (use kubectl version):
• Install details (e.g. helm install args):
• Others: