ARM: dts: am335x-evm: fix number of cpsw

am335x-evm has only one CPSW external port physically wired, but DT defines
2 ext. ports. As result, PHY connection failure reported for the second
ext. port.

Update DT to reflect am335x-evm board HW configuration, and, while here,
switch to use phy-handle instead of phy_id.
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/boot/dts/am335x-evm.dts

@@ -713,6 +713,7 @@ &mac {
 	pinctrl-0 = <&cpsw_default>;
 	pinctrl-1 = <&cpsw_sleep>;
 	status = "okay";
+	slaves = <1>;
 };
 
 &davinci_mdio {
@@ -720,15 +721,14 @@ &davinci_mdio {
 	pinctrl-0 = <&davinci_mdio_default>;
 	pinctrl-1 = <&davinci_mdio_sleep>;
 	status = "okay";
-};
 
-&cpsw_emac0 {
-	phy_id = <&davinci_mdio>, <0>;
-	phy-mode = "rgmii-txid";
+	ethphy0: ethernet-phy@0 {
+		reg = <0>;
+	};
 };
 
-&cpsw_emac1 {
-	phy_id = <&davinci_mdio>, <1>;
+&cpsw_emac0 {
+	phy-handle = <&ethphy0>;
 	phy-mode = "rgmii-txid";
 };