ASoC: dt-bindings: Document support for ak4497

ak4458 driver supports also ak4497 codec.
Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/sound/ak4458.txt

@@ -4,7 +4,7 @@ This device supports I2C mode.
 
 Required properties:
 
-- compatible : "asahi-kasei,ak4458"
+- compatible : "asahi-kasei,ak4458" or "asahi-kasei,ak4497"
 - reg : The I2C address of the device for I2C
 
 Optional properties: