iwl3945: fix station stuff in RC algorithm

Probably bugs I added.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/iwlwifi/iwl-3945-rs.c b/drivers/net/wireless/iwlwifi/iwl-3945-rs.c
index bb91353..c25daec 100644
--- a/drivers/net/wireless/iwlwifi/iwl-3945-rs.c
+++ b/drivers/net/wireless/iwlwifi/iwl-3945-rs.c
@@ -826,13 +826,12 @@
 	rcu_read_lock();
 
 	sta = ieee80211_find_sta(hw, priv->stations[sta_id].sta.sta.addr);
-	psta = (void *) sta->drv_priv;
-	if (!sta || !psta) {
-		IWL_DEBUG_RATE("leave - no private rate data!\n");
+	if (!sta) {
 		rcu_read_unlock();
 		return;
 	}
 
+	psta = (void *) sta->drv_priv;
 	rs_sta = psta->rs_sta;
 
 	spin_lock_irqsave(&rs_sta->lock, flags);
@@ -856,7 +855,6 @@
 		break;
 	}
 
-	rcu_read_unlock();
 	spin_unlock_irqrestore(&rs_sta->lock, flags);
 
 	rssi = priv->last_rx_rssi;
@@ -870,6 +868,7 @@
 	IWL_DEBUG_RATE("leave: rssi %d assign rate index: "
 		       "%d (plcp 0x%x)\n", rssi, rs_sta->start_rate,
 		       iwl3945_rates[rs_sta->start_rate].plcp);
+	rcu_read_unlock();
 }
 
 int iwl3945_rate_control_register(void)