ASoC: mediatek: dt-bindings: modify machine bindings for SOF

Add SOF related field.
1. Add a property "mediatek,adsp", Only when adsp phandle could be
retrieved, from DTS, the SOF related part of machine driver is executed.
2. Add a property "mediatek,dai-link" to support dai-links could be
specified from DTS

Signed-off-by: chunxu.li <[e-mail]>
Acked-by: Krzysztof Kozlowski <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Mark Brown <[e-mail]>

Documentation/devicetree/bindings/sound/mt8186-mt6366-da7219-max98357.yaml

···
     required:
       - sound-dai
 
+  mediatek,adsp:
+    $ref: /schemas/types.yaml#/definitions/phandle
+    description: The phandle of MT8186 ADSP platform.
+
+  mediatek,dai-link:
+    $ref: /schemas/types.yaml#/definitions/string-array
+    description:
+      A list of the desired dai-links in the sound card. Each entry is a
+      name defined in the machine driver.
+
 additionalProperties: false
 
 required: