net/mlx4_core: set port QoS attributes

Adding QoS firmware commands:
- mlx4_en_SET_PORT_PRIO2TC - set UP <=> TC
- mlx4_en_SET_PORT_SCHEDULER - set promised BW, max BW and PG number

Signed-off-by: Amir Vadai <amirv@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>