Automatic merge from submit-queue
kubenet: Fix host port for rktnetes.
Because rkt pod runs after plugin.SetUpPod() is called, so
getRunningPods() does not return the newly created pod, which
causes the hostport iptable rules to be missing for this new pod.
cc @dcbw @freehan
A follow up fix for https://github.com/kubernetes/kubernetes/pull/27878#issuecomment-227898936