vif_plugging_timeout = 0 should mean endless retry
vif_plugging_timeout = 0 should mean endless retry

Change-Id: I46fdce711c89a75576753e0741c4d052fa614d81
Closes-bug: #1612566

celebdor/kuryr-libnetwork,celebdor/kuryr-libnetwork,celebdor/kuryr-libnetwork