USB: correct locking in gadgetfs_disconnect

This patch moves spin_lock (&dev->lock) before first use of dev.
I think that test to the state of device should be protected with
this spin_lock...

Signed-off-by: Milan Svoboda <msvoboda@ra.rockwell.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/gadget/inode.c

@@ -1696,16 +1696,17 @@ gadgetfs_disconnect (struct usb_gadget *gadget)
 {
 	struct dev_data		*dev = get_gadget_data (gadget);
 
+	spin_lock (&dev->lock);
 	if (dev->state == STATE_UNCONNECTED) {
 		DBG (dev, "already unconnected\n");
-		return;
+		goto exit;
 	}
 	dev->state = STATE_UNCONNECTED;
 
 	INFO (dev, "disconnected\n");
-	spin_lock (&dev->lock);
 	next_event (dev, GADGETFS_DISCONNECT);
 	ep0_readable (dev);
+exit:
 	spin_unlock (&dev->lock);
 }