ASoC: sta32x: Convert to direct regmap API usage.

use the regmap API directly rather than relying on the snd_soc_read/write
functions as this seems to be in accordance with common practice.

Signed-off-by: Thomas Niederprüm <niederp@physik.uni-kl.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/sound/soc/codecs/Kconfig b/sound/soc/codecs/Kconfig
index 8349f98..27e1e3b 100644
--- a/sound/soc/codecs/Kconfig
+++ b/sound/soc/codecs/Kconfig
@@ -581,6 +581,7 @@
 
 config SND_SOC_STA32X
 	tristate
+	select REGMAP_I2C
 
 config SND_SOC_STA350
 	tristate "STA350 speaker amplifier"