arm64: dts: rockchip: Add rk3308 IO voltage domains

Add a disabled RK3308 IO voltage domains node to SoC DT.
Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Link: https://lore.kernel.org/r/20240521211029.1236094-12-jonas@kwiboo.seSigned-off-by: Heiko Stuebner <heiko@sntech.de>

arch/arm64/boot/dts/rockchip/rk3308.dtsi

@@ -173,6 +173,11 @@ grf: grf@ff000000 {
 		compatible = "rockchip,rk3308-grf", "syscon", "simple-mfd";
 		reg = <0x0 0xff000000 0x0 0x08000>;
 
+		io_domains: io-domains {
+			compatible = "rockchip,rk3308-io-voltage-domain";
+			status = "disabled";
+		};
+
 		reboot-mode {
 			compatible = "syscon-reboot-mode";
 			offset = <0x500>;