ALSA: hda - Merge alc*_parse_auto_config() functions in patch_realtek.c

Now all alc*_parse_auto_config() do almost same thing except for the
NID list to ignore and the PINs for SSID-check, we can merge all these
to a single function.  A good amount of code reduction.

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