ath9k: reserve a beacon slot on beaconing vif addition

The beaconing vif addition is based on max beacon slot
available. So it is better to reserve a beacon slot
on interface addition and let it be configured properly
on bss_info change.

Signed-off-by: Rajkumar Manoharan <rmanoharan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath/ath9k/main.c

@@ -1419,9 +1419,7 @@ static void ath9k_do_vif_add_setup(struct ieee80211_hw *hw,
 		 * there.
 		 */
 		error = ath_beacon_alloc(sc, vif);
-		if (error)
-			ath9k_reclaim_beacon(sc, vif);
-		else
+		if (!error)
 			ath_beacon_config(sc, vif);
 	}
 }