riscv: dts: spacemit: Add USB2 PHY node for K1

K1's DWC3 USB 3.0 controller requires two separate PHYs to function:
the USB 3.0 combophy (for SuperSpeed) and a USB 2.0 PHY (for High-Speed,
Full-Speed, etc.).

Add node for this second USB 2.0 PHY (usbphy2).

Tested-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Ze Huang <huang.ze@linux.dev>
Reviewed-by: Yixun Lan <dlan@gentoo.org>
Link: https://lore.kernel.org/r/20260111-k1-usb3dts-v2-v3-1-f5ebd546e904@linux.dev
Signed-off-by: Yixun Lan <dlan@gentoo.org>

Author: Sutter099

arch/riscv/boot/dts/spacemit/k1.dtsi

@@ -429,6 +429,14 @@
 			status = "disabled";
 		};
 
+		usbphy2: phy@c0a30000 {
+			compatible = "spacemit,k1-usb2-phy";
+			reg = <0x0 0xc0a30000 0x0 0x200>;
+			clocks = <&syscon_apmu CLK_USB30>;
+			#phy-cells = <0>;
+			status = "disabled";
+		};
+
 		combo_phy: phy@c0b10000 {
 			compatible = "spacemit,k1-combo-phy";
 			reg = <0x0 0xc0b10000 0x0 0x1000>;