rt2x00: Add skb descriptor

Use the skb->cb field to add a frame description that can be used
to transfer information passed each rt2x00 layer. This reduces the
required arguments for rt2x00lib_write_tx_desc().

Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/wireless/rt2x00/rt2x00.h b/drivers/net/wireless/rt2x00/rt2x00.h
index b2283ce..31e48c2 100644
--- a/drivers/net/wireless/rt2x00/rt2x00.h
+++ b/drivers/net/wireless/rt2x00/rt2x00.h
@@ -901,9 +901,7 @@
  * TX descriptor initializer
  */
 void rt2x00lib_write_tx_desc(struct rt2x00_dev *rt2x00dev,
-			     __le32 *txd,
-			     struct ieee80211_hdr *ieee80211hdr,
-			     unsigned int length,
+			     struct sk_buff *skb,
 			     struct ieee80211_tx_control *control);
 
 /*