Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions here: https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md.

Hide & warn on GA & deprecated feature gates

**What this PR does / why we need it**:

1. Hide GA & deprecated feature gates from the help text
2. Print a warning when GA & deprecated feature gates are explicitly set

**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
For #46404

**Special notes for your reviewer**:

I need to add to my list of things I dislike about glog that it is impossible to test.

**Release note**:
```release-note
NONE
```

/kind cleanup