ASoC: Davinci: McBSP: add device tree support for McBSP

This adds DT support for the TI DA8xx/OMAP-L1x/AM17xx/AM18xx McBSP driver.

Signed-off-by: Petr Kulhavy <petr@barix.com>
Reviewed-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/sound/soc/davinci/Kconfig b/sound/soc/davinci/Kconfig
index 50ca291..6b732d8 100644
--- a/sound/soc/davinci/Kconfig
+++ b/sound/soc/davinci/Kconfig
@@ -16,7 +16,11 @@
 	  - DRA7xx family
 
 config SND_DAVINCI_SOC_I2S
-	tristate
+	tristate "DaVinci Multichannel Buffered Serial Port (McBSP) support"
+	depends on SND_EDMA_SOC
+	help
+	  Say Y or M here if you want to have support for McBSP IP found in
+	  Texas Instruments DaVinci DA850 SoCs.
 
 config SND_DAVINCI_SOC_MCASP
 	tristate "Multichannel Audio Serial Port (McASP) support"