ALSA: hda - automute via amp instead of pinctl on some AIO models

On some AIO (All In One) models with the codec alc668
(Vendor ID: 0x10ec0668) on it, when we plug a headphone into the jack,
the system will switch the output to headphone and set the speaker to
automute as well as change the speaker Pin-ctls from 0x40 to 0x00,
this will bring loud noise to the headphone.

I tried to disable the corresponding EAPD, but it did not help to
eliminate the noise.

According to Takashi's suggestion, we use amp operation to replace the
pinctl modification for the automute, this really eliminate the noise.

BugLink: https://bugs.launchpad.net/bugs/1268468


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