phy: ocelot-serdes: convert to use eth phy mode and submode

Convert ocelot-serdes PHY driver to use recently introduced
PHY_MODE_ETHERNET and phy_set_mode_ext().

Cc: Quentin Schulz <quentin.schulz@bootlin.com>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Reviewed-by: Quentin Schulz <quentin.schulz@bootlin.com>
Tested-by: Quentin Schulz <quentin.schulz@bootlin.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
diff --git a/drivers/net/ethernet/mscc/ocelot.c b/drivers/net/ethernet/mscc/ocelot.c
index 3238b9e..3edb608 100644
--- a/drivers/net/ethernet/mscc/ocelot.c
+++ b/drivers/net/ethernet/mscc/ocelot.c
@@ -472,7 +472,6 @@ static int ocelot_port_open(struct net_device *dev)
 {
 	struct ocelot_port *port = netdev_priv(dev);
 	struct ocelot *ocelot = port->ocelot;
-	enum phy_mode phy_mode;
 	int err;
 
 	/* Enable receiving frames on the port, and activate auto-learning of
@@ -484,12 +483,8 @@ static int ocelot_port_open(struct net_device *dev)
 			 ANA_PORT_PORT_CFG, port->chip_port);
 
 	if (port->serdes) {
-		if (port->phy_mode == PHY_INTERFACE_MODE_SGMII)
-			phy_mode = PHY_MODE_SGMII;
-		else
-			phy_mode = PHY_MODE_QSGMII;
-
-		err = phy_set_mode(port->serdes, phy_mode);
+		err = phy_set_mode_ext(port->serdes, PHY_MODE_ETHERNET,
+				       port->phy_mode);
 		if (err) {
 			netdev_err(dev, "Could not set mode of SerDes\n");
 			return err;