ALSA: hda - add dock support for Thinkpad T430

ALSA: hda - add dock support for Thinkpad T430

I have a Lenovo ThinkPad T430 and an UltraBase Series 3 docking
station.

Without this patch, if I plug my headphones into the jack on the
computer, everything works fine. The computer speakers mute and the
audio is played in the headphones. However, if I plug into the docking
station headphone jack the computer speakers are muted but there is no
audio in the headphones.

Addresses https://bugs.launchpad.net/bugs/1060372

Signed-off-by: Joseph Salisbury <joseph.salisbury@canonical.com>
Cc: stable@vger.kernel.org
Signed-off-by: Takashi Iwai <tiwai@suse.de>