Description of problem:
The event for Pod consuming a readonly PVC is not clear

Version-Release number of selected component (if applicable):
4.8.0-0.nightly-2021-03-06-055252

How reproducible:
Always

Steps to Reproduce:
1. Create a storageclass with:
$ cat sc-mountoptions.yaml 
kind: StorageClass
apiVersion: storage.k8s.io/v1
metadata:
  name: ebs-sc
provisioner: ebs.csi.aws.com
parameters:
  csi.storage.k8s.io/fstype: xfs
volumeBindingMode: WaitForFirstConsumer
mountOptions:
  - ro

2. Create a PVC with this SC
3. Create a Pod consuming this PVC

Actual results:
Pod is not running and reports events:
Warning  FailedMount             <invalid> (x5 over <invalid>)  kubelet                  MountVolume.MountDevice failed for volume "pvc-a3ff0dc5-ae56-4215-8689-a09ca9354f35" : rpc error: code = Internal desc = could not format "/dev/nvme1n1" and mount it at "/var/lib/kubelet/plugins/kubernetes.io/csi/pv/pvc-a3ff0dc5-ae56-4215-8689-a09ca9354f35/globalmount"


For the in-tree plugin the event is clearer:
Warning  FailedMount             50s (x10 over 5m9s)  kubelet                  MountVolume.MountDevice failed for volume "pvc-41ff9ef1-1d9d-4c1d-8e7d-e0a5d1bd0816" : cannot mount unformatted disk /dev/nvme1n1 as we are manipulating it in read-only mode


Expected results:
Report clear events like in-tree plugin.

Master Log:

Node Log (of failed PODs):

PV Dump:

PVC Dump:

StorageClass Dump (if StorageClass used by PV/PVC):

Additional info: