ARM: dts: imx28-evk: Use pinctrl for gpio-led

Since commit 8fe4554f (leds: leds-gpio: adopt pinctrl support) gpio-led driver
has pinctrl support, so setup the gpio led pin via pinctrl and avoid the
following warning:

leds-gpio leds.12: pins are not configured from the driver
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>

arch/arm/boot/dts/imx28-evk.dts

@@ -76,7 +76,6 @@ hog_pins_a: hog@0 {
 						0x20c3 /* MX28_PAD_SSP1_SCK__GPIO_2_12 */
 						0x31c3 /* MX28_PAD_PWM3__GPIO_3_28 */
 						0x31e3 /* MX28_PAD_LCD_RESET__GPIO_3_30 */
-						0x3053 /* MX28_PAD_AUART1_TX__GPIO_3_5 */
 						0x3083 /* MX28_PAD_AUART2_RX__GPIO_3_8 */
 						0x3093 /* MX28_PAD_AUART2_TX__GPIO_3_9 */
 					>;
@@ -85,6 +84,16 @@ hog_pins_a: hog@0 {
 					fsl,pull-up = <0>;
 				};
 
+				led_pin_gpio3_5: led_gpio3_5@0 {
+					reg = <0>;
+					fsl,pinmux-ids = <
+						0x3053 /* MX28_PAD_AUART1_TX__GPIO_3_5 */
+					>;
+					fsl,drive-strength = <0>;
+					fsl,voltage = <1>;
+					fsl,pull-up = <0>;
+				};
+
 				gpmi_pins_evk: gpmi-nand-evk@0 {
 					reg = <0>;
 					fsl,pinmux-ids = <
@@ -288,6 +297,8 @@ sound {
 
 	leds {
 		compatible = "gpio-leds";
+		pinctrl-names = "default";
+		pinctrl-0 = <&led_pin_gpio3_5>;
 
 		user {
 			label = "Heartbeat";