dt-bindings: mmc: fsl-imx-esdhc: Add some compatible fallbacks

Currently make dtbs_check shows lots of errors because imx*.dtsi does
not use single compatibles but combinations of them.

Add fallbacks for imx6sll/ull which are useful for U-Boot.

This will significantly reduce noise on make dtbs_check.

Signed-off-by: Andreas Kemnade <andreas@kemnade.info>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230115195212.2530087-1-andreas@kemnade.info
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Documentation/devicetree/bindings/mmc/fsl-imx-esdhc.yaml

@@ -29,9 +29,7 @@ properties:
           - fsl,imx53-esdhc
           - fsl,imx6q-usdhc
           - fsl,imx6sl-usdhc
-          - fsl,imx6sll-usdhc
           - fsl,imx6sx-usdhc
-          - fsl,imx6ull-usdhc
           - fsl,imx7d-usdhc
           - fsl,imx7ulp-usdhc
           - fsl,imx8mm-usdhc
@@ -40,6 +38,11 @@ properties:
       - items:
           - const: fsl,imx50-esdhc
           - const: fsl,imx53-esdhc
+      - items:
+          - enum:
+              - fsl,imx6sll-usdhc
+              - fsl,imx6ull-usdhc
+          - const: fsl,imx6sx-usdhc
       - items:
           - const: fsl,imx7d-usdhc
           - const: fsl,imx6sl-usdhc