Automatic merge from submit-queue (batch tested with PRs 63291, 63490, 60445, 63507, 63524). 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>.
Deprecate in-tree OpenStack cloud provider
**What this PR does / why we need it**:
Warn operators and users to switch to the external cloud provider
for openstack.
**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
OpenStack built-in cloud provider is now deprecated. Please use the external cloud provider for OpenStack.
```
084e068406