Use Go canonical import paths

Add canonical imports only in existing doc.go files.
https://golang.org/doc/go1.4#canonicalimports

Fixes #29014

pkg/kubelet/qos/doc.go

@@ -22,4 +22,4 @@ limitations under the License.
 // when available.
 // Best-Effort containers, which don’t specify a request, can use resources only if not being used
 // by other pods.
-package qos
+package qos // import "k8s.io/kubernetes/pkg/kubelet/qos"