rtl8187: implement conf_tx callback to configure tx queues

Add conf_tx callback and use it to configure tx queues of 8187L/8187B.

Tested-by: Larry Finger <Larry.Finger@lwfinger.net>
Tested-by: Hin-Tak Leung <htl10@users.sourceforge.net>
Signed-off-by: Herton Ronaldo Krzesinski <herton@mandriva.com.br>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/rtl818x/rtl8187.h b/drivers/net/wireless/rtl818x/rtl8187.h
index 33725d0..f09872e 100644
--- a/drivers/net/wireless/rtl818x/rtl8187.h
+++ b/drivers/net/wireless/rtl818x/rtl8187.h
@@ -111,6 +111,8 @@
 	u8 signal;
 	u8 quality;
 	u8 noise;
+	u8 slot_time;
+	u8 aifsn[4];
 };
 
 void rtl8187_write_phy(struct ieee80211_hw *dev, u8 addr, u32 data);