iwlegacy: use correct structure type name in sizeof

Correct typo in the name of the type given to sizeof.  Because it is the
size of a pointer that is wanted, the typo has no impact on compilation or
execution.

This problem was found using Coccinelle (http://coccinelle.lip6.fr/).  The
semantic patch used can be found in message 0 of this patch series.
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

drivers/net/wireless/iwlegacy/common.c

@@ -2980,7 +2980,8 @@ il_tx_queue_alloc(struct il_priv *il, struct il_tx_queue *txq, u32 id)
 	/* Driver ilate data, only for Tx (not command) queues,
 	 * not shared with device. */
 	if (id != il->cmd_queue) {
-		txq->skbs = kcalloc(TFD_QUEUE_SIZE_MAX, sizeof(struct skb *),
+		txq->skbs = kcalloc(TFD_QUEUE_SIZE_MAX,
+				    sizeof(struct sk_buff *),
 				    GFP_KERNEL);
 		if (!txq->skbs) {
 			IL_ERR("Fail to alloc skbs\n");