apiserver: add localhost to alternateDNS for IPv6
apiserver: add localhost to alternateDNS for IPv6

apiserver adds localhost to the alternateDNS field
if the bind address is 0.0.0.0.
This PR considers the IPv6 unspecified address too.

Kubernetes-commit: 29ec87f769c6494fad5c0a0c624efe2dc6eeab13

kubernetes/apiserver,kubernetes/apiserver