ARM: dts: imx6ul-evk: Use WDOG_B pin reset

imx6ul-evk has WDOG1_B pin connected to the PMIC.

Pass the 'fsl,ext-reset-output' property so that the watchdog
can trigger a system POR reset via the PMIC.
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm/boot/dts/imx6ul-14x14-evk.dts

@@ -256,6 +256,12 @@ &usdhc2 {
 	status = "okay";
 };
 
+&wdog1 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_wdog>;
+	fsl,ext-reset-output;
+};
+
 &iomuxc {
 	pinctrl-names = "default";
 
@@ -484,4 +490,10 @@ MX6UL_PAD_NAND_DATA02__USDHC2_DATA2 0x17059
 			MX6UL_PAD_NAND_DATA03__USDHC2_DATA3 0x17059
 		>;
 	};
+
+	pinctrl_wdog: wdoggrp {
+		fsl,pins = <
+			MX6UL_PAD_LCD_RESET__WDOG1_WDOG_ANY    0x30b0
+		>;
+	};
 };