ALSA: hda - one Dell machine needs the headphone white noise fixup

The fixup ALC292_FIXUP_DISABLE_AAMIX can fix the white noise of
the headphone on this Dell machine.

Cc: <stable@vger.kernel.org>
Signed-off-by: Hui Wang <hui.wang@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>