Removed invalid references to slave_dig_outs inside the S/PDIF IN capture switch
control. Beforehand this was basically a mute switch for the S/PDIF outs as well.
Signed-off-by: Matthew Ranostay <mranostay@embeddedalley.com> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Jaroslav Kysela <perex@perex.cz>