Automatic merge from submit-queue. 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 SupportIPVSProxyMode feature gate in kubeadm.
**What this PR does / why we need it**:
Since #55972 gets merged, kubeadm now supports using kube-proxy ComponentConfig. Then `SupportIPVSProxyMode` feature gate can be configured in kube-proxy config. There is no need to config the feature gate in kubeadm (workaround introduced by #53962). The benefit of removing it I can think of is that we don't need to care about the IPVS feature evolution in kubeadm any longer.
**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 https://github.com/kubernetes/kubeadm/issues/512
**Special notes for your reviewer**:
/cc @luxas @Lion-Wei @kubernetes/sig-cluster-lifecycle-pr-reviews
**Release note**:
```release-note
NONE
```