ALSA: move dmaengine implementation from ASoC to ALSA core

For the PXA DMA rework, we need the generic dmaengine implementation
that currently lives in sound/soc for standalone (non-ASoC) AC'97
support.

Move it to sound/core, and rename the Kconfig symbol.

Signed-off-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
diff --git a/sound/core/Kconfig b/sound/core/Kconfig
index c0c2f57..94ce1c4 100644
--- a/sound/core/Kconfig
+++ b/sound/core/Kconfig
@@ -6,6 +6,9 @@
 	tristate
 	select SND_TIMER
 
+config SND_DMAENGINE_PCM
+	bool
+
 config SND_HWDEP
 	tristate