net/mlx5: modify TCP header using Direct Verbs

net/mlx5: modify TCP header using Direct Verbs

This patch implements additional actions of packet header
modifications.

Add actions:
- INC_TCP_SEQ - Increase sequence number in the outermost TCP header.
- DEC_TCP_SEQ - Decrease sequence number in the outermost TCP header.
- INC_TCP_ACK - Increase acknowledgment number in the outermost TCP
		header.
- DEC_TCP_ACK - Decrease acknowledgment number in the outermost TCP
		header.

Original work by Xiaoyu Min.

Signed-off-by: Dekel Peled <dekelp@mellanox.com>
Acked-by: Viacheslav Ovsiienko <viacheslavo@mellanox.com>
Acked-by: Adrien Mazarguil <adrien.mazarguil@6wind.com>