ASoC: dt-bindings: audio-graph-port: enable both flag/phandle for bitclock/frame-master

snd_soc_daifmt_parse_clock_provider_raw() is handling both
bitclock/frame-master, and is supporting both flag/phandle.
Current DT is assuming it is flag style.
This patch allows both case.
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20211216000018.2641925-1-kuninori.morimoto.gx@renesas.comSigned-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/sound/audio-graph-port.yaml

@@ -42,10 +42,15 @@ patternProperties:
         $ref: /schemas/types.yaml#/definitions/flag
       frame-master:
         description: Indicates dai-link frame master.
-        $ref: /schemas/types.yaml#/definitions/phandle
+        oneOf:
+          - $ref: /schemas/types.yaml#/definitions/flag
+          - $ref: /schemas/types.yaml#/definitions/phandle
       bitclock-master:
         description: Indicates dai-link bit clock master
-        $ref: /schemas/types.yaml#/definitions/phandle
+        oneOf:
+          - $ref: /schemas/types.yaml#/definitions/flag
+          - $ref: /schemas/types.yaml#/definitions/phandle
+
       dai-format:
         description: audio format.
         items: