After DAC assignment fix in ALC883, the 6stack-hp model is now the same
as 6stack-dig. So just remove 6stack-hp model and replace its use with
6stack-dig.
Signed-off-by: NHerton Ronaldo Krzesinski <herton@mandriva.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>