dt-bindings: i2c: Add S700 support for Actions Semi Soc's

Add s700 compatible string to Actions Semi SoC dt-bindings.
Signed-off-by: Parthiban Nallathambi <pn@denx.de>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Documentation/devicetree/bindings/i2c/i2c-owl.txt

@@ -2,7 +2,9 @@ Actions Semiconductor Owl I2C controller
 
 Required properties:
 
-- compatible        : Should be "actions,s900-i2c".
+- compatible        : Should be one of the following:
+		      - "actions,s700-i2c" for S700 SoC
+		      - "actions,s900-i2c" for S900 SoC
 - reg               : Offset and length of the register set for the device.
 - #address-cells    : Should be 1.
 - #size-cells       : Should be 0.