mlxsw: spectrum: Configure learning for VLAN-aware bridge port

We are going to prevent the device from generating learning
notifications for a port that was configured with learning disabled.

Since learning configuration is done per {Port, VID} we need to apply
the port's learning configuration for any VID that is added to the
bridge port's VLAN filter list.

When a VID is added to the VLAN filter list of a VLAN-aware bridge port,
configure the {Port, VID} learning status according to the port's
configuration. When the VID is removed, disable learning for the {Port,
VID}.

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>