[ALSA] sound/usb/usbaudio: Handle return value of usb_register()

Handle the return value of usb_register() in the module_init function.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>
diff --git a/sound/usb/usbaudio.c b/sound/usb/usbaudio.c
index 67202b9..3d7f36f 100644
--- a/sound/usb/usbaudio.c
+++ b/sound/usb/usbaudio.c
@@ -3577,8 +3577,7 @@
 		printk(KERN_WARNING "invalid nrpacks value.\n");
 		return -EINVAL;
 	}
-	usb_register(&usb_audio_driver);
-	return 0;
+	return usb_register(&usb_audio_driver);
 }