Merge pull request #32745 from abrarshivani/vsphere_storage_class

Automatic merge from submit-queue

Support for storage class for vSphere volume plugin. Custom disk format for dynamic provisioning.

This PR does following,

1.  Add support for storage class for vSphere volume plugin.
2. Add option for user to provision disk with different disk formats. Format choices are
    "thin" (default), "zeroedthick", "eagerzeroedthick".

Sample storageclass (yaml):
```
kind: StorageClass
apiVersion: storage.k8s.io/v1beta1
metadata:
  name: slow
provisioner: kubernetes.io/vsphere-volume
parameters:
  diskformat: thin
```

examples/experimental/persistent-volume-provisioning/README.md

@@ -83,6 +83,21 @@ parameters:
 * `type`: `pd-standard` or `pd-ssd`. Default: `pd-ssd`
 * `zone`: GCE zone. If not specified, a random zone in the same region as controller-manager will be chosen.
 
+#### vSphere
+
+```yaml
+kind: StorageClass
+apiVersion: storage.k8s.io/v1beta1
+metadata:
+  name: slow
+provisioner: kubernetes.io/vsphere-volume
+parameters:
+  diskformat: thin
+```
+
+* `diskformat`: `thin`, `zeroedthick` and `eagerzeroedthick`. See vSphere docs for details. Default: `"thin"`.
+
+
 #### GLUSTERFS
 
 ```yaml