ARM: dts: imx6qdl-udoo: Add Pincfgs for UART4

Add Pincfgs for UART4 to enable Communication with the onboard SAM3X
Signed-off-by: Markus Kueffner <kueffner.markus@gmail.com>
Reviewed-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm/boot/dts/imx6qdl-udoo.dtsi

@@ -195,6 +195,13 @@ MX6QDL_PAD_EIM_D27__UART2_RX_DATA	0x1b0b1
 			>;
 		};
 
+		pinctrl_uart4: uart4grp {
+			fsl,pins = <
+				MX6QDL_PAD_KEY_COL0__UART4_TX_DATA	0x1b0b1
+				MX6QDL_PAD_KEY_ROW0__UART4_RX_DATA	0x1b0b1
+			>;
+		};
+
 		pinctrl_usbh: usbhgrp {
 			fsl,pins = <
 				MX6QDL_PAD_GPIO_17__GPIO7_IO12 0x80000000
@@ -265,6 +272,12 @@ &uart2 {
 	status = "okay";
 };
 
+&uart4 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_uart4>;
+	status = "okay";
+};
+
 &usbh1 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&pinctrl_usbh>;