Automatic merge from submit-queue (batch tested with PRs 61608, 62304). 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>.
Remove isNotDir error check
**What this PR does / why we need it**:
This check was supposed to handle the "subpath file" scenario, but:
1. It's wrong (should have been !)
2. It's not needed anymore. `IsLikelyNotMountPoint` was fixed to handle file mounts via https://github.com/kubernetes/kubernetes/pull/58433
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```