ARM: sun6i: colombus: Add uart0 muxing

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>

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

@@ -24,6 +24,8 @@ chosen {
 
 	soc@01c00000 {
 		uart0: serial@01c28000 {
+			pinctrl-names = "default";
+			pinctrl-0 = <&uart0_pins_a>;
 			status = "okay";
 		};
 	};