ASoC: sunxi: fix a sound binding broken reference

Address this rename:
	Documentation/devicetree/bindings/sound/{sun4i-i2s.txt -> allwinner,sun4i-a10-i2s.yaml}

Fixes: 0a0ca8e9 ("dt-bindings: sound: Convert Allwinner I2S binding to YAML")
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Link: https://lore.kernel.org/r/9932608f32030c886d906ea656eda8408c544776.1564140865.git.mchehab+samsung@kernel.orgSigned-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/sound/sun8i-a33-codec.txt

@@ -4,7 +4,7 @@ Allwinner SUN8I audio codec
 On Sun8i-A33 SoCs, the audio is separated in different parts:
 	  - A DAI driver. It uses the "sun4i-i2s" driver which is
 	  documented here:
-	  Documentation/devicetree/bindings/sound/sun4i-i2s.txt
+	  Documentation/devicetree/bindings/sound/allwinner,sun4i-a10-i2s.yaml
 	  - An analog part of the codec which is handled as PRCM registers.
 	  See Documentation/devicetree/bindings/sound/sun8i-codec-analog.txt
 	  - An digital part of the codec which is documented in this current