ARM: sunxi: dt: declare the r_pio pin controller for A31 SoC

The A31 SoC has a different pin controller for PL and PM banks.
Define this new controller in the device tree.
Signed-off-by: NBoris BREZILLON <boris.brezillon@free-electrons.com>
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>

arch/arm/boot/dts/sun6i-a31.dtsi

@@ -734,5 +734,19 @@
 			compatible = "allwinner,sun6i-a31-cpuconfig";
 			reg = <0x01f01c00 0x300>;
 		};
+
+		r_pio: pinctrl@01f02c00 {
+			compatible = "allwinner,sun6i-a31-r-pinctrl";
+			reg = <0x01f02c00 0x400>;
+			interrupts = <0 45 4>,
+				     <0 46 4>;
+			clocks = <&apb0_gates 0>;
+			resets = <&apb0_rst 0>;
+			gpio-controller;
+			interrupt-controller;
+			#address-cells = <1>;
+			#size-cells = <0>;
+			#gpio-cells = <3>;
+		};
 	};
 };