ALSA: hda - Fixing speaker noise on the two latest thinkpad models

We have two latest thinkpad laptop models which are all based on the
Intel skylake platforms, and all of them have the codec alc293 on
them. When the machines boot to the desktop, an greeting dialogue
shows up with the notification sound. But on these two models, there
is noise with the notification sound. We have 3 SKUs for each of
the models, all of them have this problem.

So far, this problem is only specific to these two thinkpad models,
we did not find this problem on the old thinkpad models with the
codec alc293 or alc292.

A workaround for this problem is disabling the aamix.

Cc: stable@vger.kernel.org
BugLink: https://bugs.launchpad.net/bugs/1523517


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