net/mlx4_en: Create new header file for all statistics info

Add mlx4_stats.h file and move there all statistics structs and marcos.

Signed-off-by: Eran Ben Elisha <eranbe@mellanox.com>
Signed-off-by: Hadar Hen Zion <hadarh@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --cc drivers/net/ethernet/mellanox/mlx4/en_ethtool.c
Simple merge

diff --cc drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
Simple merge

diff --cc drivers/net/ethernet/mellanox/mlx4/mlx4_stats.h
Simple merge

diff --cc drivers/net/ethernet/mellanox/mlx4/port.c
Simple merge