Don't write multicast related data to the HW when mc is disabled.
Also, don't allocate mid id to new mids (so the remove function could know
that they weren't wrote to the HW)
Signed-off-by: NNogah Frankel <nogahf@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>