dt-bindings: mmc: JZ4740: Add bindings for JZ4775

Add a compatible to the mmc DT bindings for the JZ4775 SoC from Ingenic.
Signed-off-by: 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com>
Acked-by: Paul Cercueil <paul@crapouillou.net>
Link: https://lore.kernel.org/r/1623329930-14387-2-git-send-email-zhouyanjie@wanyeetech.comSigned-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Documentation/devicetree/bindings/mmc/ingenic,mmc.yaml

@@ -19,6 +19,7 @@ properties:
           - ingenic,jz4740-mmc
           - ingenic,jz4725b-mmc
           - ingenic,jz4760-mmc
+          - ingenic,jz4775-mmc
           - ingenic,jz4780-mmc
           - ingenic,x1000-mmc
       - items: