When dumping the hardware FDB we should report entries pointing to VLAN
devices with VLAN 0, as packets coming into the bridge are untagged.
Likewise, pass FDB_{ADD,DEL} notifications with VLAN 0 for these
devices.

Fixes: 54a73201 ("mlxsw: spectrum: Adjust switchdev ops for VLAN devices")
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>