rt2x00: Implement set_tim callback for all drivers

Implement set_tim callback for all rt2x00 drivers, this makes the
device wake up powersaving stations properly while in AP mode.

The only way to update the beacon is by simply calling mac80211 and
requesting the new beacon. This means the set_tim() event is mostly the
same as a beacon_done() event which was already defined in rt2x00lib.

Signed-off-by: Stefan Steuerwald <salsasepp@googlemail.com>
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/rt2x00/rt2x00.h b/drivers/net/wireless/rt2x00/rt2x00.h
index 71f37cb..3e17717 100644
--- a/drivers/net/wireless/rt2x00/rt2x00.h
+++ b/drivers/net/wireless/rt2x00/rt2x00.h
@@ -963,6 +963,8 @@
 				unsigned int changed_flags,
 				unsigned int *total_flags,
 				int mc_count, struct dev_addr_list *mc_list);
+int rt2x00mac_set_tim(struct ieee80211_hw *hw, struct ieee80211_sta *sta,
+		      bool set);
 #ifdef CONFIG_RT2X00_LIB_CRYPTO
 int rt2x00mac_set_key(struct ieee80211_hw *hw, enum set_key_cmd cmd,
 		      struct ieee80211_vif *vif, struct ieee80211_sta *sta,