Fixed mic input with STAC92xx codecs.  The mic pin was sometimes set to
OUTPUT by the headphone jack detection.
Also, try to assign a secondary mic as front-mic (or vice versa)
in the auto-detection if possible.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>