[ALSA] hda-codec - More fix of ALC880 codec support

Documentation,HDA Codec driver,HDA generic driver,HDA Intel driver
- Fix some invalid configurations, typos in the last patch
- Make init_verbs chainable, so that different configs can share the same
  init_verbs
- Reorder and clean up the source codes in patch_realtek.c
- Add the pin default configuration parser, used commonly in cmedia
  and realtek patch codes.
- Add 'auto' model to ALC880 for auto-configuration from BIOS
  Use this model as default, and 3-stack as fallback

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