Automatic merge from submit-queue
Adding Flexvolume plugin dir piping for controller manager on COS
**What this PR does / why we need it**: Sets the default Flexvolume plugin directory correctly for controller manager running on COS images.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes#51563
```release-note
NONE
```
/release-note-none
/sig storage
/assign @msau42
/cc @wongma7
2e69d4e625