ASoC: dt-bindings: samsung,arndale: document ALC5631

The Arndale audio complex might come with ALC5631 which is compatible
with RT5631.  Document the compatible since it is used in Linux kernel
sources.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Acked-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220129122430.45694-2-krzysztof.kozlowski@canonical.comSigned-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/sound/samsung,arndale.yaml

@@ -13,6 +13,7 @@ maintainers:
 properties:
   compatible:
     enum:
+      - samsung,arndale-alc5631
       - samsung,arndale-rt5631
       - samsung,arndale-wm1811