ASoC: bindings: fsl-asoc-card: add compatible string for TLV320AIC32x4 codec

The TLV320AIC32x4 is commonly used on TQ-Systems starterkit mainboards
for i.MX-based SoMs (i.MX6Q/DL, i.MX6UL, i.MX7) and LS1021A.
Signed-off-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Acked-by: Nicolin Chen <nicoleotsuka@gmail.com>
Link: https://lore.kernel.org/r/20200821071153.7317-1-matthias.schiffer@ew.tq-group.comSigned-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/sound/fsl-asoc-card.txt

@@ -38,6 +38,8 @@ The compatible list for this generic sound card currently:
 
  "fsl,imx-audio-wm8524"
 
+ "fsl,imx-audio-tlv320aic32x4"
+
 Required properties:
 
   - compatible		: Contains one of entries in the compatible list.