Merge pull request #24756 from euank/rkt-fix-os-arg

Automatic merge from submit-queue

rkt: Pass through os argument

This was lost in a rebase in #24496 and, while not required to build, is
required to function correctly under rkt (else panics!)

cc @yifan-gu

pkg/kubelet/rkt/rkt.go

@@ -199,6 +199,7 @@ func New(
 		livenessManager:     livenessManager,
 		volumeGetter:        volumeGetter,
 		execer:              execer,
+		os:                  os,
 		touchPath:           touchPath,
 	}