mac80211: move TX info into skb->cb

This patch converts mac80211 and all drivers to have transmit
information and status in skb->cb rather than allocating extra
memory for it and copying all the data around. To make it fit,
a union is used where only data that is necessary for all steps
is kept outside of the union.

A number of fixes were done by Ivo, as well as the rt2x00 part
of this patch.

Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/b43/pio.h

@@ -62,8 +62,6 @@ struct b43_pio_txpacket {
 	struct b43_pio_txqueue *queue;
 	/* The TX data packet. */
 	struct sk_buff *skb;
-	/* The status meta data. */
-	struct ieee80211_tx_status txstat;
 	/* Index in the (struct b43_pio_txqueue)->packets array. */
 	u8 index;
 
@@ -167,8 +165,7 @@ int b43_pio_init(struct b43_wldev *dev);
 void b43_pio_stop(struct b43_wldev *dev);
 void b43_pio_free(struct b43_wldev *dev);
 
-int b43_pio_tx(struct b43_wldev *dev,
-	       struct sk_buff *skb, struct ieee80211_tx_control *ctl);
+int b43_pio_tx(struct b43_wldev *dev, struct sk_buff *skb);
 void b43_pio_handle_txstatus(struct b43_wldev *dev,
 			     const struct b43_txstatus *status);
 void b43_pio_get_tx_stats(struct b43_wldev *dev,
@@ -193,8 +190,7 @@ static inline void b43_pio_stop(struct b43_wldev *dev)
 {
 }
 static inline int b43_pio_tx(struct b43_wldev *dev,
-			     struct sk_buff *skb,
-			     struct ieee80211_tx_control *ctl)
+			     struct sk_buff *skb)
 {
 	return 0;
 }