Added a dmux to the STAC9228 cards with DMIC support. And added a
STAC_DIGITAL_INPUT_SOURCE macro for repeating mixer code.
Signed-off-by: NMatthew Ranostay <mranostay@embeddedalley.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>
Signed-off-by: NJaroslav Kysela <perex@perex.cz>