ASoC: OMAP4: omap-dmic: Initial support for OMAP DMIC

Add support for OMAP4 Digital Microphone interface.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/sound/soc/omap/Kconfig b/sound/soc/omap/Kconfig
index fe83d0d..052254a 100644
--- a/sound/soc/omap/Kconfig
+++ b/sound/soc/omap/Kconfig
@@ -2,6 +2,9 @@
 	tristate "SoC Audio for the Texas Instruments OMAP chips"
 	depends on ARCH_OMAP
 
+config SND_OMAP_SOC_DMIC
+	tristate
+
 config SND_OMAP_SOC_MCBSP
 	tristate
 	select OMAP_MCBSP