ASoC: dt-bindings: mt8188-mt6359: add es8326 support

Add compatible string "mediatek,mt8188-es8326" to support new board
with es8326 codec.
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Rui Zhou <zhourui@huaqin.corp-partner.google.com>
Link: https://msgid.link/r/20231212123050.4080083-2-zhourui@huaqin.corp-partner.google.comSigned-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/sound/mediatek,mt8188-mt6359.yaml

@@ -15,6 +15,7 @@ allOf:
 properties:
   compatible:
     enum:
+      - mediatek,mt8188-es8326
       - mediatek,mt8188-mt6359-evb
       - mediatek,mt8188-nau8825
       - mediatek,mt8188-rt5682s