Add a codec driver for SI476X MFD

This commit add a sound codec driver for Silicon Laboratories 476x
series of AM/FM radio chips.

Signed-off-by: Andrey Smirnov <andrey.smirnov@convergeddevices.net>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/sound/soc/codecs/Kconfig b/sound/soc/codecs/Kconfig
index b92759a..6f4f284 100644
--- a/sound/soc/codecs/Kconfig
+++ b/sound/soc/codecs/Kconfig
@@ -54,6 +54,7 @@
 	select SND_SOC_PCM3008
 	select SND_SOC_RT5631 if I2C
 	select SND_SOC_SGTL5000 if I2C
+	select SND_SOC_SI476X if MFD_SI476X_CORE
 	select SND_SOC_SN95031 if INTEL_SCU_IPC
 	select SND_SOC_SPDIF
 	select SND_SOC_SSM2602 if SND_SOC_I2C_AND_SPI
@@ -277,6 +278,9 @@
 config SND_SOC_SGTL5000
 	tristate
 
+config SND_SOC_SI476X
+	tristate
+
 config SND_SOC_SIGMADSP
 	tristate
 	select CRC32