The i.MX 8 DTSes use two compatibles so update the binding to fix
dtbs_check warnings like:
  arch/arm64/boot/dts/freescale/imx8mn-evk.dt.yaml: mmc@
30b40000:
    compatible: ['fsl,imx8mn-usdhc', 'fsl,imx7d-usdhc'] is too long
    From schema: Documentation/devicetree/bindings/mmc/fsl-imx-esdhc.yaml
  arch/arm64/boot/dts/freescale/imx8mn-evk.dt.yaml: mmc@
30b40000:
    compatible: Additional items are not allowed ('fsl,imx7d-usdhc' was unexpected)
  arch/arm64/boot/dts/freescale/imx8mn-ddr4-evk.dt.yaml: mmc@
30b40000:
    compatible: ['fsl,imx8mn-usdhc', 'fsl,imx7d-usdhc'] is too long
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20200829062505.4642-1-krzk@kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
     };
 
     mmc@5b010000 {
-        compatible = "fsl,imx8qxp-usdhc";
+        compatible = "fsl,imx8qxp-usdhc", "fsl,imx7d-usdhc";
         interrupts = <GIC_SPI 232 IRQ_TYPE_LEVEL_HIGH>;
         reg = <0x5b010000 0x10000>;
         clocks = <&conn_lpcg IMX_CONN_LPCG_SDHC0_IPG_CLK>,
 
 
 properties:
   compatible:
-    enum:
-      - fsl,imx25-esdhc
-      - fsl,imx35-esdhc
-      - fsl,imx51-esdhc
-      - fsl,imx53-esdhc
-      - fsl,imx6q-usdhc
-      - fsl,imx6sl-usdhc
-      - fsl,imx6sx-usdhc
-      - fsl,imx6ull-usdhc
-      - fsl,imx7d-usdhc
-      - fsl,imx7ulp-usdhc
-      - fsl,imx8mq-usdhc
-      - fsl,imx8mm-usdhc
-      - fsl,imx8mn-usdhc
-      - fsl,imx8mp-usdhc
-      - fsl,imx8qm-usdhc
-      - fsl,imx8qxp-usdhc
+    oneOf:
+      - enum:
+          - fsl,imx25-esdhc
+          - fsl,imx35-esdhc
+          - fsl,imx51-esdhc
+          - fsl,imx53-esdhc
+          - fsl,imx6q-usdhc
+          - fsl,imx6sl-usdhc
+          - fsl,imx6sx-usdhc
+          - fsl,imx6ull-usdhc
+          - fsl,imx7d-usdhc
+          - fsl,imx7ulp-usdhc
+      - items:
+          - enum:
+              - fsl,imx8mm-usdhc
+              - fsl,imx8mn-usdhc
+              - fsl,imx8mp-usdhc
+              - fsl,imx8mq-usdhc
+              - fsl,imx8qxp-usdhc
+          - const: fsl,imx7d-usdhc
 
   reg:
     maxItems: 1