Since we currently do not support the offloading of 802.1D bridges, we
need to be able to let the device know it should not learn MAC addresses
on specific {Port, VID} pairs.

Add the SPVMLR register, which controls the learning enablement of
{Port, VID} pairs.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>