Automatic merge from submit-queue (batch tested with PRs 52662, 53547, 53588, 53573, 53599). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
Use const instead of hard code for volume plugin
**What this PR does / why we need it**:
nits: cleanup hard-coded volume plugin name
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```