net: dsa: mv88e6xxx: restore VLANTable map control

The In Chip Port Based VLAN Table contains bits used to restrict which
output ports this input port can send frames to.

With the VLAN filtering enabled, these tables work in conjunction with
the VLAN Table Unit to allow egressing frames.

In order to remove the current dependency to BRIDGE_VLAN_FILTERING for
basic hardware bridging to work, it is necessary to restore a fine
control of each port's VLANTable, on setup and when a port joins or
leaves a bridge.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>