arm64: dts: imx8mn: Enable HS400-ES

The SDHC controller in the imx8mn has the same controller
as the imx8mm which supports HS400-ES. Change the compatible
fallback to imx8mm to enable it, but keep the imx7d-usdhc
to prevent breaking backwards compatibility.
Signed-off-by: Adam Ford <aford173@gmail.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm64/boot/dts/freescale/imx8mn.dtsi

@@ -933,7 +933,7 @@ mu: mailbox@30aa0000 {
 			};
 
 			usdhc1: mmc@30b40000 {
-				compatible = "fsl,imx8mn-usdhc", "fsl,imx7d-usdhc";
+				compatible = "fsl,imx8mn-usdhc", "fsl,imx8mm-usdhc", "fsl,imx7d-usdhc";
 				reg = <0x30b40000 0x10000>;
 				interrupts = <GIC_SPI 22 IRQ_TYPE_LEVEL_HIGH>;
 				clocks = <&clk IMX8MN_CLK_IPG_ROOT>,
@@ -947,7 +947,7 @@ usdhc1: mmc@30b40000 {
 			};
 
 			usdhc2: mmc@30b50000 {
-				compatible = "fsl,imx8mn-usdhc", "fsl,imx7d-usdhc";
+				compatible = "fsl,imx8mn-usdhc", "fsl,imx8mm-usdhc", "fsl,imx7d-usdhc";
 				reg = <0x30b50000 0x10000>;
 				interrupts = <GIC_SPI 23 IRQ_TYPE_LEVEL_HIGH>;
 				clocks = <&clk IMX8MN_CLK_IPG_ROOT>,
@@ -961,7 +961,7 @@ usdhc2: mmc@30b50000 {
 			};
 
 			usdhc3: mmc@30b60000 {
-				compatible = "fsl,imx8mn-usdhc", "fsl,imx7d-usdhc";
+				compatible = "fsl,imx8mn-usdhc", "fsl,imx8mm-usdhc", "fsl,imx7d-usdhc";
 				reg = <0x30b60000 0x10000>;
 				interrupts = <GIC_SPI 24 IRQ_TYPE_LEVEL_HIGH>;
 				clocks = <&clk IMX8MN_CLK_IPG_ROOT>,