ALSA: hda - Refactor ALC269 power-ups/downs in PM callbacks

Create a helper function to simplify the code.
Also, cleaned up the ifdef SND_HDA_NEEDS_RESUME and
CONFIG_SND_HDA_POWER_SAVE.  The former is always defined when the latter
is set.

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