net/mlx4_core: Add timestamping device capability

Add new device capability for timestamping support and query FW to retrieve it.

Signed-off-by: Eugenia Emantayev <eugenia@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Amir Vadai <amirv@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/mlx4/device.h

@@ -152,7 +152,8 @@ enum {
 	MLX4_DEV_CAP_FLAG2_RSS_TOP		= 1LL <<  1,
 	MLX4_DEV_CAP_FLAG2_RSS_XOR		= 1LL <<  2,
 	MLX4_DEV_CAP_FLAG2_FS_EN		= 1LL <<  3,
-	MLX4_DEV_CAP_FLAGS2_REASSIGN_MAC_EN	= 1LL <<  4
+	MLX4_DEV_CAP_FLAGS2_REASSIGN_MAC_EN	= 1LL <<  4,
+	MLX4_DEV_CAP_FLAG2_TS			= 1LL <<  5
 };
 
 enum {