ARM: dts: imx7d-pico: Add watchdog support

imx7d-pico has the WDOG1_B pin connected to the PMIC, so add the
wdog1 node and use the 'fsl,ext-reset-output' property to
properly describe it.
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm/boot/dts/imx7d-pico.dts

@@ -284,6 +284,13 @@ &usdhc3 {
 	status = "okay";
 };
 
+&wdog1 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_wdog>;
+	fsl,ext-reset-output;
+	status = "okay";
+};
+
 &iomuxc {
 	pinctrl_enet1: enet1grp {
 		fsl,pins = <
@@ -385,3 +392,11 @@ MX7D_PAD_SD3_DATA7__SD3_DATA7		0x5b
 		>;
 	};
 };
+
+&iomuxc_lpsr {
+	pinctrl_wdog: wdoggrp {
+		fsl,pins = <
+			MX7D_PAD_LPSR_GPIO1_IO00__WDOD1_WDOG_B	0x74
+		>;
+	};
+};