ALSA: hda: Add Samsung R720 SSID for subwoofer pin fixup

BugLink: https://launchpad.net/bugs/677830
The original reporter states that the subwoofer does not mute when
inserting headphones.  We need an entry for his machine's SSID in the
subwoofer pin fixup list, so add it there (verified using hda_analyzer).

Reported-and-tested-by: i-NoD
Cc: <stable@kernel.org>
Signed-off-by: Daniel T Chen <crimsun@ubuntu.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>