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.se
Signed-off-by: Heiko Stuebner <heiko@sntech.de>

[ upstream commit: d1829ba469d5743734e37d59fece73e3668ab084 ]

(cherry picked from commit cebde305971e33a76efc3280e09814499ef89f54)
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
diff --git a/dts/upstream/src/arm64/rockchip/rk3308.dtsi b/dts/upstream/src/arm64/rockchip/rk3308.dtsi
index 6531ede..31c25de 100644
--- a/dts/upstream/src/arm64/rockchip/rk3308.dtsi
+++ b/dts/upstream/src/arm64/rockchip/rk3308.dtsi
@@ -173,6 +173,11 @@
 		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>;