ARM: dts: imx6: RDU2: detail USDHC description

None of the slots support 1.8V signaling or SDIO. There is no point in
probing for a SD card on the eMMC controller.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm/boot/dts/imx6qdl-zii-rdu2.dtsi

@@ -602,6 +602,8 @@ &usdhc2 {
 	wp-gpios = <&gpio2 3 GPIO_ACTIVE_HIGH>;
 	vmmc-supply = <&reg_3p3v_sd>;
 	vqmmc-supply = <&reg_3p3v>;
+	no-1-8-v;
+	no-sdio;
 	status = "okay";
 };
 
@@ -613,6 +615,8 @@ &usdhc3 {
 	wp-gpios = <&gpio2 1 GPIO_ACTIVE_HIGH>;
 	vmmc-supply = <&reg_3p3v_sd>;
 	vqmmc-supply = <&reg_3p3v>;
+	no-1-8-v;
+	no-sdio;
 	status = "okay";
 };
 
@@ -622,7 +626,10 @@ &usdhc4 {
 	bus-width = <8>;
 	vmmc-supply = <&reg_3p3v>;
 	vqmmc-supply = <&reg_3p3v>;
+	no-1-8-v;
 	non-removable;
+	no-sdio;
+	no-sd;
 	status = "okay";
 };