net/mlx5e: Disable client vlan TX acceleration

We need to resolve a HW configuration issue for enabling HW CVLAN
insertion. Meanwhile, no need to implement the VLAN insertion in
the driver, rather use the generic kernel VLAN insertion method.

Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>