Subsequent patches are going to replace the current default VID (1) with
VLAN_N_VID - 1 (4095).

Prepare for this conversion by replacing the hard-coded '1' with a
define.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Reviewed-by: NPetr Machata <petrm@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>