spin_unlock_bh(&txq->lock) already disables softirqs so we don't want
to do it here.  Fixes smatch warnings:
   drivers/net/wireless/ath/ath5k/base.c:1048 ath5k_drain_tx_buffs() error: double lock 'bottom_half:'
   drivers/net/wireless/ath/ath5k/base.c:1056 ath5k_drain_tx_buffs() error: double unlock 'bottom_half:'
Reported-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Bob Copeland <me@bobcopeland.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
 
                                ath5k_txbuf_free_skb(ah, bf);
 
-                               spin_lock_bh(&ah->txbuflock);
+                               spin_lock(&ah->txbuflock);
                                list_move_tail(&bf->list, &ah->txbuf);
                                ah->txbuf_len++;
                                txq->txq_len--;
-                               spin_unlock_bh(&ah->txbuflock);
+                               spin_unlock(&ah->txbuflock);
                        }
                        txq->link = NULL;
                        txq->txq_poll_mark = false;