Automatic merge from submit-queue (batch tested with PRs 52445, 52380, 52516, 52531, 52538). 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>..
Follow go style guide and fix versioning doc link
Signed-off-by: sakeven <jc5930@sina.cn>
**What this PR does / why we need it**:
1. Follow go style guide
* should drop = "" from declaration of var gitMajor; it is the zero value
* should omit type string from declaration of var gitVersion; it will be inferred from the right-hand side
2. Fix versioning doc link.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
**Special notes for your reviewer**:
**Release note**:
```
NONE
```