This patch adds the missing flag to enable "Mute-LED Mode" mixer enum
ctl for Thinkpads that have also the software mute-LED control.
Reported-and-tested-by: NPali Rohár <pali.rohar@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>