ALSA: hda - Add 5stack-no-fp model for STAC927x

The recent fix for the headphone volume control on IDT/STAC codecs
resulted in the removal of invalid "Side" volume eventually.  But,
if the front panel doesn't exist, this setup could be regarded as a
sort of regression, as reported in kernel bug #13250.

Now as a workaround, a new model 5stack-no-fp is added so that the user
without the front panel can choose this one explicitly.

Reference: bko#13250
	http://bugzilla.kernel.org/show_bug.cgi?id=13250

Signed-off-by: Takashi Iwai <tiwai@suse.de>