arm64: dts: imx8mq-librem5: delay the startup of the SDIO

The redpine wifi card takes some time to wake up. Wait for it.
Signed-off-by: Angus Ainslie <angus@akkea.ca>
Signed-off-by: Martin Kepplinger <martin.kepplinger@puri.sm>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm64/boot/dts/freescale/imx8mq-librem5.dtsi

@@ -1212,6 +1212,7 @@ &usdhc2 {
 	pinctrl-2 = <&pinctrl_usdhc2_200mhz>;
 	bus-width = <4>;
 	vmmc-supply = <&reg_wifi_3v3>;
+	post-power-on-delay-ms = <1000>;
 	cd-gpios = <&gpio2 12 GPIO_ACTIVE_LOW>;
 	disable-wp;
 	cap-sdio-irq;