mlxsw: spectrum_flower: Disallow usage of vlan_id key on egress

As recent spectrum FW imposes a limitation on using vlan_id key for
egress ACL, disallow the usage of that key accordingly and return a
proper extack message.

Signed-off-by: Nir Dotan <nird@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>