BugLink: http://bugs.launchpad.net/bugs/1578798

commit 037e1197 upstream.

Fixes audio output on a ThinkPad X260, when using Lenovo CES 2013
docking station series (basic, pro, ultra).
Signed-off-by: Conrad Kostecki <ck+linuxkernel@bl4ckb0x.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>