net/mlx4_en: Add Flow control statistics display via ethtool

Flow control per priority and Global pause counters are now visible via
ethtool.  The counters shows statistics regarding pauses in the device.

Signed-off-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Shani Michaeli <shanim@mellanox.com>
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 --git a/include/linux/mlx4/device.h b/include/linux/mlx4/device.h
index 49abbe2..ab7ebec 100644
--- a/include/linux/mlx4/device.h
+++ b/include/linux/mlx4/device.h
@@ -205,7 +205,8 @@
 	MLX4_DEV_CAP_FLAG2_RECOVERABLE_ERROR_EVENT = 1LL << 20,
 	MLX4_DEV_CAP_FLAG2_PORT_REMAP		= 1LL <<  21,
 	MLX4_DEV_CAP_FLAG2_QCN			= 1LL <<  22,
-	MLX4_DEV_CAP_FLAG2_QP_RATE_LIMIT	= 1LL <<  23
+	MLX4_DEV_CAP_FLAG2_QP_RATE_LIMIT	= 1LL <<  23,
+	MLX4_DEV_CAP_FLAG2_FLOWSTATS_EN         = 1LL <<  24
 };
 
 enum {