ALSA: hda - Disable widget power-save for VIA codecs

The widget power-save that was enabled in 4.1 kernel seems resulting
in the silent output on VIA codecs by some reason.  Some widgets get
wrong power states.

As a quick fix, turn this flag off while keeping power_down_unused
flag.  This will bring back to the state of 4.0.x.

Fixes: 688b12cc ('ALSA: hda - Use the new power control for VIA codecs')
Reported-and-tested-by: Harald Dunkel <harri@afaics.de>
Cc: <stable@vger.kernel.org> # v4.1
Signed-off-by: Takashi Iwai <tiwai@suse.de>