arm64: tegra: Enable card detect for SD card on P2888

Now that we have a GPIO controller, enable the card detect GPIO for
the SD card slot.
Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

arch/arm64/boot/dts/nvidia/tegra194-p2888.dtsi

@@ -33,9 +33,7 @@ serial@3110000 {
 
 		/* SDMMC1 (SD/MMC) */
 		sdhci@3400000 {
-/*
 			cd-gpios = <&gpio TEGRA194_MAIN_GPIO(A, 0) GPIO_ACTIVE_LOW>;
-*/
 		};
 
 		/* SDMMC4 (eMMC) */