mlxsw: spectrum_switchdev: Update the mdb of mrouter port change

Whenever a port starts / stops being mrouter, update all the mdb entries
in the HW to flood / stop flooding mc packets there.
The change should happen only if the port is not in the mid. (If it is,
the mid should flood mc packets to this port anyway)

Signed-off-by: Nogah Frankel <nogahf@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>