USB: audio gadget: free alsa devices when unloading

Signed-off-by: Cliff Cai <cliff.cai@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/gadget/u_audio.h b/drivers/usb/gadget/u_audio.h
index cc8d159..08ffce3 100644
--- a/drivers/usb/gadget/u_audio.h
+++ b/drivers/usb/gadget/u_audio.h
@@ -51,6 +51,6 @@
 };
 
 int gaudio_setup(struct gaudio *card);
-void gaudio_cleanup(struct gaudio *card);
+void gaudio_cleanup(void);
 
 #endif /* __U_AUDIO_H */