Automatic merge from submit-queue (batch tested with PRs 57954, 62166). 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>. clean up useless func in pkg/kubelet/network/plugins.go **What this PR does / why we need it**: clean up useless func in pkg/kubelet/network/plugins.go **Release note**: ```release-note ```NONE