ASoC: Add ak4642/ak4643 codec support

This is very simple driver for ALSA
It supprt headphone output and stereo input only
This patch is tested by ms7724se

Signed-off-by: Kuninori Morimoto <morimoto.kuninori@renesas.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/sound/soc/codecs/Kconfig b/sound/soc/codecs/Kconfig
index 167a5ce..0edca93 100644
--- a/sound/soc/codecs/Kconfig
+++ b/sound/soc/codecs/Kconfig
@@ -18,6 +18,7 @@
 	select SND_SOC_AD73311 if I2C
 	select SND_SOC_AK4104 if SPI_MASTER
 	select SND_SOC_AK4535 if I2C
+	select SND_SOC_AK4642 if I2C
 	select SND_SOC_CS4270 if I2C
 	select SND_SOC_MAX9877 if I2C
 	select SND_SOC_PCM3008
@@ -92,6 +93,9 @@
 config SND_SOC_AK4535
 	tristate
 
+config SND_SOC_AK4642
+	tristate
+
 # Cirrus Logic CS4270 Codec
 config SND_SOC_CS4270
 	tristate