[ALSA] aoa: fix a sparse warning

This fixes a warning sparse gives.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>

sound/aoa/soundbus/core.c

@@ -163,8 +163,6 @@ static int soundbus_device_resume(struct device * dev)
 
 #endif /* CONFIG_PM */
 
-extern struct device_attribute soundbus_dev_attrs[];
-
 static struct bus_type soundbus_bus_type = {
 	.name		= "aoa-soundbus",
 	.probe		= soundbus_probe,

sound/aoa/soundbus/soundbus.h

@@ -199,4 +199,6 @@ struct soundbus_driver {
 extern int soundbus_register_driver(struct soundbus_driver *drv);
 extern void soundbus_unregister_driver(struct soundbus_driver *drv);
 
+extern struct device_attribute soundbus_dev_attrs[];
+
 #endif /* __SOUNDBUS_H */