ALSA: hda/realtek - Reuse init_hook for ALC269VB coef setup

Move the currently unused spec->init_hook at the beginning of the init
sequence so that the recently added ALC269VB coef setup can be put
there.  The alc_init() is again clean without an ugly check.

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