Merge branch 'ovs-notifications'

Nicolas Dichtel says:

====================
ovs: fix rtnl notifications on interface deletion

There was no rtnl notifications for interfaces (gre, vxlan, geneve) created
by ovs. This problem is fixed by adjusting the creation path.

v1 -> v2:
 - add patch #1 and #4
 - rework error handling in patch #2
====================

Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>