Add support for the mono mux on several 92HD7xxx codecs.
Creates a dynamic mixer for the mux selection.
Signed-off-by: NMatthew Ranostay <mranostay@embeddedalley.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>
Signed-off-by: NJaroslav Kysela <perex@perex.cz>