chore(eks): clarified the usage of the vpcSubnets property (#17420)

Closes #17023.

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packages/@aws-cdk/aws-eks/README.md

@@ -102,8 +102,8 @@ The following is a qualitative diagram of the various possible components involv
 
 ```text
  +-----------------------------------------------+               +-----------------+
-  | EKS Cluster | kubectl |  |
-  | ----------- |<-------------+| Kubectl Handler |
+ |                 EKS Cluster                   |    kubectl    |                 |
+ |-----------------------------------------------|<-------------+| Kubectl Handler |
  |                                               |               |                 |
  |                                               |               +-----------------+
  | +--------------------+    +-----------------+ |
@@ -516,6 +516,9 @@ new eks.Cluster(this, 'HelloEKS', {
 
 If you do not specify a VPC, one will be created on your behalf, which you can then access via `cluster.vpc`. The cluster VPC will be associated to any EKS managed capacity (i.e Managed Node Groups and Fargate Profiles).
 
+Please note that the `vpcSubnets` property defines the subnets where EKS will place the _control plane_ ENIs. To choose
+the subnets where EKS will place the worker nodes, please refer to the **Provisioning clusters** section above.
+
 If you allocate self managed capacity, you can specify which subnets should the auto-scaling group use:
 
 ```ts