remove bitfields from struct ieee80211_tx_packet_data

[Johannes: completely clear flags in ieee80211_remove_tx_extra]
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Michael Wu <flamingice@sourmilk.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>