[ALSA] Add comments for 

Sound Core
Added (minimal) comments for  in Kconfig, so that
configurators can choose this entry explicitly.

A more descriptive comment by someone else is appreciated...

Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/Kconfig b/sound/Kconfig
index 047d59e..fe175151 100644
--- a/sound/Kconfig
+++ b/sound/Kconfig
@@ -42,6 +42,11 @@
 config SND
 	tristate "Advanced Linux Sound Architecture"
 	depends on SOUND
+	help
+	  Say 'Y' or 'M' to enable ALSA (Advanced Linux Sound Architecture),
+	  the new base sound system.
+
+	  For more information, see http://www.alsa-project.org/
 
 source "sound/core/Kconfig"