staging: gdm72xx: use list_move instead of list_del/list_add

Using list_move() instead of list_del() + list_add().

spatch with a semantic match is used to found this problem.
(http://coccinelle.lip6.fr/)
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/gdm72xx/gdm_usb.c

@@ -186,8 +186,7 @@ static struct usb_rx *get_rx_struct(struct rx_cxt *rx)
 /* Before this function is called, spin lock should be locked. */
 static void put_rx_struct(struct rx_cxt *rx, struct usb_rx *r)
 {
-	list_del(&r->list);
-	list_add(&r->list, &rx->free_list);
+	list_move(&r->list, &rx->free_list);
 }
 
 static int init_usb(struct usbwm_dev *udev)