rt2x00: Remove unused variable frame_control from rt2x00mac_tx.

As additional fallout also remove the also unused variable ieee80211hdr.
Reported-by: Johannes Stezenbach <js@sig21.net>
Signed-off-by: Gertjan van Wingerde <gwingerde@gmail.com>
Acked-by: Ivo van Doorn <ivdoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/rt2x00/rt2x00mac.c

@@ -103,10 +103,8 @@ int rt2x00mac_tx(struct ieee80211_hw *hw, struct sk_buff *skb)
 {
 	struct rt2x00_dev *rt2x00dev = hw->priv;
 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
-	struct ieee80211_hdr *ieee80211hdr = (struct ieee80211_hdr *)skb->data;
 	enum data_queue_qid qid = skb_get_queue_mapping(skb);
 	struct data_queue *queue;
-	u16 frame_control;
 
 	/*
 	 * Mac80211 might be calling this function while we are trying
@@ -141,7 +139,6 @@ int rt2x00mac_tx(struct ieee80211_hw *hw, struct sk_buff *skb)
 	 * either RTS or CTS-to-self frame and handles everything
 	 * inside the hardware.
 	 */
-	frame_control = le16_to_cpu(ieee80211hdr->frame_control);
 	if ((tx_info->control.rates[0].flags & (IEEE80211_TX_RC_USE_RTS_CTS |
 						IEEE80211_TX_RC_USE_CTS_PROTECT)) &&
 	    !rt2x00dev->ops->hw->set_rts_threshold) {