ARM: dts: imx7s-warp: Fix watchdog pinmux

The watchdog pin is controlled by the iomuxc_lpsr, not the regular
iomux, so move it there.
Signed-off-by: NSascha Hauer <s.hauer@pengutronix.de>
Reviewed-by: NFabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: NShawn Guo <shawnguo@kernel.org>

arch/arm/boot/dts/imx7s-warp.dts

@@ -437,7 +437,9 @@
 			MX7D_PAD_SD3_RESET_B__SD3_RESET_B	0x1b
 		>;
 	};
+};
 
+&iomuxc_lpsr {
 	pinctrl_wdog: wdoggrp {
 		fsl,pins = <
 			MX7D_PAD_GPIO1_IO00__WDOD1_WDOG_B	0x74