[ALSA] hda-codec - Add support for Sigmatel STAC9202/9250/9251 codecs

This patch adds support for Gateway laptops based on the
Sigmatel STAC9250 codecs, as well as basic support for
STAC9202/9250/9251 codecs.  Some Gateway systems require
probe_mask=1 to work.  More work to be done prior to alsa 1.0.14
final.

Signed-off-by: Tobin Davis <tdavis@dsl-only.net>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>