ASoC: Add ADAU7002 Stereo PDM-to-I2S/TDM Converter driver

This patch adds support for the ADAU7002 PDM-to-I2S/TDM converter. The
ADAU7002 takes a stereo PDM signal (e.g. from two digital microphones) and
converts it into a I2S/TDM PCM stream. The chip does not have a
programmable control interface and the driver simply describes the static
capabilities of the chip.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/sound/soc/codecs/Kconfig b/sound/soc/codecs/Kconfig
index 4d82a58..9ae3c0a 100644
--- a/sound/soc/codecs/Kconfig
+++ b/sound/soc/codecs/Kconfig
@@ -32,6 +32,7 @@
 	select SND_SOC_ADAU1977_SPI if SPI_MASTER
 	select SND_SOC_ADAU1977_I2C if I2C
 	select SND_SOC_ADAU1701 if I2C
+	select SND_SOC_ADAU7002
 	select SND_SOC_ADS117X
 	select SND_SOC_AK4104 if SPI_MASTER
 	select SND_SOC_AK4535 if I2C
@@ -322,6 +323,9 @@
 	select SND_SOC_ADAU1977
 	select REGMAP_I2C
 
+config SND_SOC_ADAU7002
+	tristate "Analog Devices ADAU7002 Stereo PDM-to-I2S/TDM Converter"
+
 config SND_SOC_ADAV80X
 	tristate