arm: dts: imx8mp-phyboard-pollux-rdk-u-boot: Add wdog pinctrl entry

Add missing pinctrl entry in spl.

Signed-off-by: Teresa Remmet <t.remmet@phytec.de>
Reviewed-by: Fabio Estevam <festevam@gmail.com>
diff --git a/arch/arm/dts/imx8mp-phyboard-pollux-rdk-u-boot.dtsi b/arch/arm/dts/imx8mp-phyboard-pollux-rdk-u-boot.dtsi
index 32ed037..dbc48df 100644
--- a/arch/arm/dts/imx8mp-phyboard-pollux-rdk-u-boot.dtsi
+++ b/arch/arm/dts/imx8mp-phyboard-pollux-rdk-u-boot.dtsi
@@ -34,6 +34,10 @@
 	u-boot,dm-spl;
 };
 
+&pinctrl_wdog {
+	u-boot,dm-spl;
+};
+
 &gpio1 {
 	u-boot,dm-spl;
 };