net/mlx5: E-Switch, Set the actions for offloaded rules properly

As for the current generation of the mlx5 HW (CX4/CX4-Lx) per flow vlan
push/pop actions are emulated, we must not program them to the firmware.

Fixes: f5f82476

 ('net/mlx5: E-Switch, Support VLAN actions in the offloads mode')
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Reported-by: Paul Blakey <paulb@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>