ARM: sun7i: a20-olinuxino: Enable the user LED

The A20-olinuxino Micro has a LED connected to the PH2 pin. Use the
gpio-led driver to enable the control over this LED.

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

arch/arm/boot/dts/sun7i-a20-olinuxino-micro.dts

@@ -19,6 +19,15 @@
 	compatible = "olimex,a20-olinuxino-micro", "allwinner,sun7i-a20";
 
 	soc@01c00000 {
+		pinctrl@01c20800 {
+			led_pins_olinuxino: led_pins@0 {
+				allwinner,pins = "PH2";
+				allwinner,function = "gpio_out";
+				allwinner,drive = <1>;
+				allwinner,pull = <0>;
+			};
+		};
+
 		uart0: serial@01c28000 {
 			pinctrl-names = "default";
 			pinctrl-0 = <&uart0_pins_a>;
@@ -37,4 +46,16 @@
 			status = "okay";
 		};
 	};
+
+	leds {
+		compatible = "gpio-leds";
+		pinctrl-names = "default";
+		pinctrl-0 = <&led_pins_olinuxino>;
+
+		green {
+			label = "a20-olinuxino-micro:green:usr";
+			gpios = <&pio 7 2 0>;
+			default-state = "on";
+		};
+	};
 };