ASoC: Add WM8961 driver

The WM8961 is a low power, high quality stereo CODEC designed for
portable digital applications with headphone and stereo class D speaker
drivers.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/sound/soc/codecs/Kconfig b/sound/soc/codecs/Kconfig
index bbc97fd..021dbdf 100644
--- a/sound/soc/codecs/Kconfig
+++ b/sound/soc/codecs/Kconfig
@@ -39,6 +39,7 @@
 	select SND_SOC_WM8903 if I2C
 	select SND_SOC_WM8940 if I2C
 	select SND_SOC_WM8960 if I2C
+	select SND_SOC_WM8961 if I2C
 	select SND_SOC_WM8971 if I2C
 	select SND_SOC_WM8988 if SND_SOC_I2C_AND_SPI
 	select SND_SOC_WM8990 if I2C
@@ -156,6 +157,9 @@
 config SND_SOC_WM8960
 	tristate
 
+config SND_SOC_WM8961
+	tristate
+
 config SND_SOC_WM8971
 	tristate