ARM: dts: imx6ull: change to use new compatible "fsl,imx6ull-usdhc" for usdhc

i.MX6ULL has errata ERR010450, there is I/O timing limitation,
for SDR mode, SD card clock can't exceed 150MHz, for DDR mode,
SD card clock can't exceed 45MHz. This patch change to use the
new compatible "fsl,imx6ull-usdhc" to follow this limitation.

Signed-off-by: Haibo Chen <[e-mail]>
Signed-off-by: Shawn Guo <[e-mail]>

arch/arm/boot/dts/imx6ull.dtsi

···
 	compatible = "fsl,imx6ull-ocotp", "syscon";
 };
 
+&usdhc1 {
+	compatible = "fsl,imx6ull-usdhc", "fsl,imx6sx-usdhc";
+};
+
+&usdhc2 {
+	compatible = "fsl,imx6ull-usdhc", "fsl,imx6sx-usdhc";
+};
+
 / {
 	soc {
 		aips3: aips-bus@2200000 {