sound: virtuoso: add Xonar DS support

Add experimental support for the Asus Xonar DS.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
diff --git a/sound/pci/Kconfig b/sound/pci/Kconfig
index 351654c..1298c68 100644
--- a/sound/pci/Kconfig
+++ b/sound/pci/Kconfig
@@ -789,6 +789,7 @@
 	  Say Y here to include support for sound cards based on the
 	  Asus AV100/AV200 chips, i.e., Xonar D1, DX, D2, D2X,
 	  Essence ST (Deluxe), and Essence STX.
+	  Support for the DS is experimental.
 	  Support for the HDAV1.3 (Deluxe) is very experimental.
 
 	  To compile this driver as a module, choose M here: the module