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>.

kubeadm: Fix a small bug in the self-hosting code

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

`apps/v1beta2` requires that `DaemonSet.spec.selector.matchLabels` equals `DaemonSet.spec.template.metadata.labels`. Without this change, the API server rejects the DaemonSet in the validation stage.

**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
```
@kubernetes/sig-cluster-lifecycle-pr-reviews @xiangpengzhao