arm64: allwinner: h6: add R_I2C controller

Allwinner H6 SoC has a R_I2C controller wired to the PL0/PL1 pins, which
are used in the reference design to connect AXP805 PMIC.

Add support for it.
Signed-off-by: NIcenowy Zheng <icenowy@aosc.io>
Signed-off-by: NMaxime Ripard <maxime.ripard@bootlin.com>

arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi

@@ -204,6 +204,24 @@
 			#gpio-cells = <3>;
 			interrupt-controller;
 			#interrupt-cells = <3>;
+
+			r_i2c_pins: r-i2c {
+				pins = "PL0", "PL1";
+				function = "s_i2c";
+			};
+		};
+
+		r_i2c: i2c@7081400 {
+			compatible = "allwinner,sun6i-a31-i2c";
+			reg = <0x07081400 0x400>;
+			interrupts = <GIC_SPI 107 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&r_ccu 8>;
+			resets = <&r_ccu 4>;
+			pinctrl-names = "default";
+			pinctrl-0 = <&r_i2c_pins>;
+			status = "disabled";
+			#address-cells = <1>;
+			#size-cells = <0>;
 		};
 	};
 };