rt2x00: Fix regression for rt2500pci

Since commit:
     commit f1aa4c54
     Author: Ivo van Doorn <ivdoorn@gmail.com>
     Date:   Tue Jun 29 21:38:55 2010 +0200

     rt2x00: Write the BSSID to register when interface is added

mananged mode in rt2500pci was broken, due to intf->bssid containing
random data rather then the expected 00:00:00:00:00:00

This is corrected by sending the BSSID to rt2x00lib_config_intf
only in AP mode where the bssid is set to a valid value.
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Acked-by: Helmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/rt2x00/rt2x00mac.c

@@ -273,17 +273,24 @@ int rt2x00mac_add_interface(struct ieee80211_hw *hw,
 	mutex_init(&intf->beacon_skb_mutex);
 	intf->beacon = entry;
 
-	if (vif->type == NL80211_IFTYPE_AP)
-		memcpy(&intf->bssid, vif->addr, ETH_ALEN);
-	memcpy(&intf->mac, vif->addr, ETH_ALEN);
-
 	/*
 	 * The MAC adddress must be configured after the device
 	 * has been initialized. Otherwise the device can reset
 	 * the MAC registers.
+	 * The BSSID address must only be configured in AP mode,
+	 * however we should not send an empty BSSID address for
+	 * STA interfaces at this time, since this can cause
+	 * invalid behavior in the device.
 	 */
-	rt2x00lib_config_intf(rt2x00dev, intf, vif->type,
-			      intf->mac, intf->bssid);
+	memcpy(&intf->mac, vif->addr, ETH_ALEN);
+	if (vif->type == NL80211_IFTYPE_AP) {
+		memcpy(&intf->bssid, vif->addr, ETH_ALEN);
+		rt2x00lib_config_intf(rt2x00dev, intf, vif->type,
+				      intf->mac, intf->bssid);
+	} else {
+		rt2x00lib_config_intf(rt2x00dev, intf, vif->type,
+				      intf->mac, NULL);
+	}
 
 	/*
 	 * Some filters depend on the current working mode. We can force