ALSA: virtuoso: Xonar DSX support

This patch adds support for ASUS - Xonar DSX sound cards. Tested on
openSUSE 12.2 with kernel:
Linux 3.4.6-2.10-desktop #1 SMP PREEMPT Thu Jul 26 09:36:26 UTC 2012 (641c197) x86_64 x86_64 x86_64 GNU/Linux
Works:
 - play sounds
 - adjust volume on master channel.
 - mute .

Since Xonar DS uses the same chip, everything that works for DS should
work for DSX as well.

Signed-off-by: Sergiu Giurgiu <sgiurgiu11@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/pci/oxygen/xonar_wm87x6.c b/sound/pci/oxygen/xonar_wm87x6.c
index 63cff90..b555b62 100644
--- a/sound/pci/oxygen/xonar_wm87x6.c
+++ b/sound/pci/oxygen/xonar_wm87x6.c
@@ -1255,7 +1255,6 @@
 }
 
 static const struct oxygen_model model_xonar_ds = {
-	.shortname = "Xonar DS",
 	.longname = "Asus Virtuoso 66",
 	.chip = "AV200",
 	.init = xonar_ds_init,
@@ -1327,6 +1326,11 @@
 	switch (id->subdevice) {
 	case 0x838e:
 		chip->model = model_xonar_ds;
+		chip->model.shortname = "Xonar DS";
+		break;
+	case 0x8522:
+		chip->model = model_xonar_ds;
+		chip->model.shortname = "Xonar DSX";
 		break;
 	case 0x835e:
 		chip->model = model_xonar_hdav_slim;