ath9k: use ETH_P_PAE

It was being discussed where we would put this, but now it found a home
so use its define.
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath9k/xmit.c

@@ -178,7 +178,7 @@ static void fill_min_rates(struct sk_buff *skb, struct ath_tx_control *txctl)
 	} else if (ieee80211_is_data(fc)) {
 		if (ieee80211_is_nullfunc(fc) ||
 				/* Port Access Entity (IEEE 802.1X) */
-			(skb->protocol == cpu_to_be16(0x888E))) {
+				(skb->protocol == cpu_to_be16(ETH_P_PAE))) {
 			txctl->use_minrate = 1;
 			txctl->min_rate = tx_info_priv->min_rate;
 		}