phy: lan966x: Extend lan966x to support multiple phy interfaces.

Currently the driver is supporting only the interfaces QSGMII, SGMII,
RGMII and GMII. This patch extend the supported interfaces with
1000BASE-X and 2500BASE-X.
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Link: https://lore.kernel.org/r/20211130101015.164916-1-horatiu.vultur@microchip.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

drivers/phy/microchip/lan966x_serdes.c

@@ -392,6 +392,10 @@ static int serdes_set_mode(struct phy *phy, enum phy_mode mode, int submode)
 	if (mode != PHY_MODE_ETHERNET)
 		return -EOPNOTSUPP;
 
+	if (submode == PHY_INTERFACE_MODE_1000BASEX ||
+	    submode == PHY_INTERFACE_MODE_2500BASEX)
+		submode = PHY_INTERFACE_MODE_SGMII;
+
 	for (i = 0; i < ARRAY_SIZE(lan966x_serdes_muxes); i++) {
 		if (macro->idx != lan966x_serdes_muxes[i].idx ||
 		    mode != lan966x_serdes_muxes[i].mode ||