Mock out tunnel_sync in test to avoid sleeping
Mock out tunnel_sync in test to avoid sleeping

The tunnel_sync call in the daemon loop for the ovs tunnel
tests blocks for 30 seconds. This patch mocks it out to stop
that.

Closes-Bug: #1340570
Change-Id: I58c3907ed564413a8251bc1bb7922e25f673db18

gkotton/vmware-nsx,gkotton/vmware-nsx