I/OAT: list usage cleanup

Trivial cleanup, list_del(); list_add_tail() is equivalent
to list_move_tail(). Semantic patch for coccinelle can be
found at www.cccmz.de/~snakebyte/list_move_tail.spatch

Signed-off-by: Eric Sesterhenn <[e-mail]>
Signed-off-by: Maciej Sosnowski <[e-mail]>
Signed-off-by: Shannon Nelson <[e-mail]>
Acked-by: Jeff Kirsher <[e-mail]>
Signed-off-by: Dan Williams <[e-mail]>

drivers/dma/ioat_dma.c

···
 				 * up if the client is done with the descriptor
 				 */
 				if (async_tx_test_ack(&desc->async_tx)) {
-					list_del(&desc->node);
-					list_add_tail(&desc->node,
-						      &ioat_chan->free_desc);
+					list_move_tail(&desc->node,
+						       &ioat_chan->free_desc);
 				} else
 					desc->async_tx.cookie = 0;
 			} else {