ASoC: omap-pcm: Convert to use dmaengine

Original author: Russell King <rmk+kernel@arm.linux.org.uk>

Switch the omap-pcm to use dmaengine.
Certain features are not supported by after dmaengine conversion:
1. No period wakeup mode
   DMA engine has no way to communicate this information through
   standard channels.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Tested-by: Janusz Krzysztofik <jkrzyszt@tis.icnet.pl>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/omap/Kconfig

 config SND_OMAP_SOC
 	tristate "SoC Audio for the Texas Instruments OMAP chips"
-	depends on ARCH_OMAP
+	depends on ARCH_OMAP && DMA_OMAP
+	select SND_SOC_DMAENGINE_PCM
 
 config SND_OMAP_SOC_DMIC
 	tristate