Merge branch 'mlxsw-Offload-bridge-device-mrouter'

Jiri Pirko says:

====================
mlxsw: Offload bridge device mrouter

Yotam says:

Similarly to a bridged port, the bridge device itself can be configured by
the user to be an mrouter port. In this case, all multicast traffic should
be forwarded to it. Make the mlxsw Spectrum driver offload these directives
to the Spectrum hardware.

Patches 1 and 2 add a new switchdev notification for bridge device mrouter
port status and make the bridge module notify about it.

Patches 3-5 change the mlxsw Spectrum driver to handle these notifications
by adding the Spectrum router port to the bridge MDB entries.

v1->v2:
 - patch1:
   - Don't add the MDB_RTR_TYPE_TEMP state and use the timer_pending to
     distinguish between learning-on and learning-off states
====================

Signed-off-by: David S. Miller <davem@davemloft.net>