ALSA: virtuoso: add Xonar Essence STX II support

Just add the PCI ID for the STX II.  It appears to work the same as the
STX, except for the addition of the not-yet-supported daughterboard.

Tested-by: Mario <fugazzi99@gmail.com>
Tested-by: corubba <corubba@gmx.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>