[ALSA] hda-codec - Fix capture mixers of ALC662 models

The commit that added support for ASUS P701 eeepc also changed the
mixers of other ALC662 models, duplicating entries for the Capture
items, making them to not work anymore. This fixes it by removing
duplicated entries using where possible the common alc662_capture_mixer.
Also alc662_capture_mixer should use alc662* functions and not alc882
(I checked /proc/asound/card0/codec* on an eepc model and it's ok).

Signed-off-by: Herton Ronaldo Krzesinski <herton@mandriva.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>