ASoC: Fix warning related to 'sound-name-prefix' binding

commit 82d3ec1d89fa ("ASoC: Use schema reference for sound-name-prefix")
added name-prefix.yaml schema and the same reference was used in couple
of other schemas. But this is causing following warning and the same is
fixed in current patch.

 Documentation/devicetree/bindings/sound/nxp,tfa989x.example.dt.yaml:
 audio-codec@34: 'sound-name-prefix' does not match any of the regexes:
 'pinctrl-[0-9]+'
  From schema: Documentation/devicetree/bindings/sound/nxp,tfa989x.yaml
 Documentation/devicetree/bindings/sound/nxp,tfa989x.example.dt.yaml:
 audio-codec@36: 'sound-name-prefix' does not match any of the regexes:
 'pinctrl-[0-9]+'
  From schema: Documentation/devicetree/bindings/sound/nxp,tfa989x.yaml

Fixes: 82d3ec1d89fa ("ASoC: Use schema reference for sound-name-prefix")
Reported-by: Rob Herring <robh+dt@kernel.org>
Suggested-by: Rob Herring <robh+dt@kernel.org>
Signed-off-by: Sameer Pujar <spujar@nvidia.com>
Link: https://lore.kernel.org/r/1632238860-16947-1-git-send-email-spujar@nvidia.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/sound/nxp,tfa989x.yaml

@@ -24,6 +24,8 @@ properties:
   '#sound-dai-cells':
     const: 0
 
+  sound-name-prefix: true
+
   vddd-supply:
     description: regulator phandle for the VDDD power supply.
 

Documentation/devicetree/bindings/sound/simple-audio-mux.yaml

@@ -24,6 +24,8 @@ properties:
     description: |
       GPIOs used to select the input line.
 
+  sound-name-prefix: true
+
 required:
   - compatible
   - mux-gpios