deploy: update fsGroupPolicy to File for nfs driver object

NFS volume similar to CephFs volumes can support
fsGroupPolicy as File, now Kubernetes Kubernetes may
use fsGroup to change permissions and ownership of the
volume to match user requested fsGroup in the pod's
SecurityPolicy regardless of fstype or access mode.

Signed-off-by: Rakshith R <rar@redhat.com>

Author: Rakshith-R

deploy/nfs/kubernetes/csidriver.yaml

@@ -14,3 +14,4 @@ spec:
   attachRequired: false
   volumeLifecycleModes:
     - Persistent
+  fsGroupPolicy: File