net/mlx5e: Replace TC VLAN pop with VLAN 0 rewrite in prio tag mode

Current ConnectX HW is unable to perform VLAN pop in TX path and VLAN
push on RX path. To workaround that limitation untagged packets are
tagged with VLAN ID 0x000 (priority tag) and pop/push actions are
replaced by VLAN re-write actions (which are supported by the HW).
Replace TC VLAN pop action with a VLAN priority tag header rewrite.

Signed-off-by: Eli Britstein <elibr@mellanox.com>
Reviewed-by: Oz Shlomo <ozsh@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>