protokube: don't try to connect to apiserver if not control-plane
protokube: don't try to connect to apiserver if not control-plane

We run protokube on the nodes in gossip mode; however protokube tries
to connect to the apiserver on localhost, and that simply won't work
if running on a node.

This doesn't cause any actual problems beyond logspam, but it's an
easy fix.

justinsb/kops,kubernetes/kops,kubernetes/kops,justinsb/kops,justinsb/kops,kubernetes/kops