mlxsw: spectrum: Notify bridge's FDB only based on learning_sync

mlxsw: spectrum: Notify bridge's FDB only based on learning_sync

When we disable learning on bridge port we should still update the
software bridge's FDB when entry pointing to this bridge port is
aged-out. We can otherwise have an inconsistency between software and
hardware tables.

Fixes: 35a6cce1f44f ("mlxsw: spectrum: Implement FDB add/remove/dump for LAG")
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>