USB: convert sound/* to use module_usb_driver()

This converts the drivers in sound/* to use the
module_usb_driver() macro which makes the code smaller and a bit
simpler.

Added bonus is that it removes some unneeded kernel log messages about
drivers loading and/or unloading.

Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Daniel Mack <zonque@gmail.com>
Cc: Clemens Ladisch <clemens@ladisch.de>
Cc: Torsten Schenk <torsten.schenk@zoho.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Karsten Wiese <fzu@wemgehoertderstaat.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/sound/usb/caiaq/device.c b/sound/usb/caiaq/device.c
index 3eb605b..457fb27 100644
--- a/sound/usb/caiaq/device.c
+++ b/sound/usb/caiaq/device.c
@@ -538,16 +538,5 @@
 	.id_table 	= snd_usb_id_table,
 };
 
-static int __init snd_module_init(void)
-{
-	return usb_register(&snd_usb_driver);
-}
-
-static void __exit snd_module_exit(void)
-{
-	usb_deregister(&snd_usb_driver);
-}
-
-module_init(snd_module_init)
-module_exit(snd_module_exit)
+module_usb_driver(snd_usb_driver);