arm64: dts: renesas: white-hawk-single: Improve Ethernet TSN description

  - Add the missing "ethernet3" alias for the Ethernet TSN port, so
    U-Boot will fill its local-mac-address property based on the
    "eth3addr" environment variable (if set), avoiding a random MAC
    address being assigned by the OS,
  - Rename the numerical Ethernet PHY label to "tsn0_phy", to avoid
    future conflicts, and for consistency with the "avbN_phy" labels.

Fixes: 3d8e475 ("arm64: dts: renesas: white-hawk-single: Wire-up Ethernet TSN")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Link: https://lore.kernel.org/367f10a18aa196ff1c96734dd9bd5634b312c421.1746624368.git.geert+renesas@glider.be

Author: geertu

arch/arm64/boot/dts/renesas/white-hawk-single.dtsi

@@ -11,6 +11,10 @@
 / {
 	model = "Renesas White Hawk Single board";
 	compatible = "renesas,white-hawk-single";
+
+	aliases {
+		ethernet3 = &tsn0;
+	};
 };
 
 &hscif0 {
@@ -53,7 +57,7 @@
 	pinctrl-0 = <&tsn0_pins>;
 	pinctrl-names = "default";
 	phy-mode = "rgmii";
-	phy-handle = <&phy3>;
+	phy-handle = <&tsn0_phy>;
 	status = "okay";
 
 	mdio {
@@ -63,7 +67,7 @@
 		reset-gpios = <&gpio1 23 GPIO_ACTIVE_LOW>;
 		reset-post-delay-us = <4000>;
 
-		phy3: ethernet-phy@0 {
+		tsn0_phy: ethernet-phy@0 {
 			compatible = "ethernet-phy-id002b.0980",
 				     "ethernet-phy-ieee802.3-c22";
 			reg = <0>;