net/mlx5e: Fix ethtool self test: link speed

Ethtool self test contains a test for link speed. This test reads the
PTYS register and determines whether the current speed is valid or not.
Change current implementation to use the function mlx5e_port_linkspeed()
that does the same check and fails when speed is invalid. This code
redundancy lead to a bug when mlx5e_port_linkspeed() was updated with
expended speeds and the self test was not.

Fixes: 2c81bfd5 ("net/mlx5e: Move port speed code from en_ethtool.c to en/port.c")
Signed-off-by: Aya Levin <ayal@mellanox.com>
Reviewed-by: Moshe Shemesh <moshe@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

drivers/net/ethernet/mellanox/mlx5/core/en_selftest.c

@@ -35,6 +35,7 @@
 #include <linux/udp.h>
 #include <net/udp.h>
 #include "en.h"
+#include "en/port.h"
 
 enum {
 	MLX5E_ST_LINK_STATE,
@@ -80,22 +81,12 @@ static int mlx5e_test_link_state(struct mlx5e_priv *priv)
 
 static int mlx5e_test_link_speed(struct mlx5e_priv *priv)
 {
-	u32 out[MLX5_ST_SZ_DW(ptys_reg)];
-	u32 eth_proto_oper;
-	int i;
+	u32 speed;
 
 	if (!netif_carrier_ok(priv->netdev))
 		return 1;
 
-	if (mlx5_query_port_ptys(priv->mdev, out, sizeof(out), MLX5_PTYS_EN, 1))
-		return 1;
-
-	eth_proto_oper = MLX5_GET(ptys_reg, out, eth_proto_oper);
-	for (i = 0; i < MLX5E_LINK_MODES_NUMBER; i++) {
-		if (eth_proto_oper & MLX5E_PROT_MASK(i))
-			return 0;
-	}
-	return 1;
+	return mlx5e_port_linkspeed(priv->mdev, &speed);
 }
 
 struct mlx5ehdr {