usb: renesas_usbhs: (cosmetic) simplify list operations

list.h already provide helpers to find the first entry and to move list
nodes to the tail of another list. This patch simply uses those helpers,
no functional changes.

Signed-off-by: Guennadi Liakhovetski <[e-mail]>
Signed-off-by: Felipe Balbi <[e-mail]>

drivers/usb/renesas_usbhs/fifo.c

···
 		pipe->handler = &usbhsf_null_handler;
 	}
 
-	list_del_init(&pkt->node);
-	list_add_tail(&pkt->node, &pipe->list);
+	list_move_tail(&pkt->node, &pipe->list);
 
 	/*
 	 * each pkt must hold own handler.
···
 	if (list_empty(&pipe->list))
 		return NULL;
 
-	return list_entry(pipe->list.next, struct usbhs_pkt, node);
+	return list_first_entry(&pipe->list, struct usbhs_pkt, node);
 }
 
 struct usbhs_pkt *usbhs_pkt_pop(struct usbhs_pipe *pipe, struct usbhs_pkt *pkt)