dt-bindings: i2c: ingenic: Add compatible string for the JZ4770

The I2C controller in the JZ4770 SoC seems to work the exact same as in
the JZ4780 SoC.

We could use "ingenic,jz4780-i2c" as a fallback string in the Device
Tree, but that would be awkward, since the JZ4780 is newer. Instead,
add a "ingenic,jz4770-i2c" string and use it as fallback for the
"ingenic,jz4780-i2c" string.
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

Documentation/devicetree/bindings/i2c/ingenic,i2c.yaml

@@ -17,9 +17,13 @@ properties:
     pattern: "^i2c@[0-9a-f]+$"
 
   compatible:
-    enum:
-      - ingenic,jz4780-i2c
-      - ingenic,x1000-i2c
+    oneOf:
+      - enum:
+        - ingenic,jz4770-i2c
+        - ingenic,x1000-i2c
+      - items:
+        - const: ingenic,jz4780-i2c
+        - const: ingenic,jz4770-i2c
 
   reg:
     maxItems: 1
@@ -60,7 +64,7 @@ examples:
     #include <dt-bindings/dma/jz4780-dma.h>
     #include <dt-bindings/interrupt-controller/irq.h>
     i2c@10054000 {
-      compatible = "ingenic,jz4780-i2c";
+      compatible = "ingenic,jz4780-i2c", "ingenic,jz4770-i2c";
       #address-cells = <1>;
       #size-cells = <0>;
       reg = <0x10054000 0x1000>;