ieee80211_add_callback
int ieee80211_add_callback(struct mbuf *m,
if (!ieee80211_add_callback(m, bar_tx_complete, tap)) {
ieee80211_add_callback(m, ieee80211_nulldata_transmitted,
ieee80211_add_callback(m, ieee80211_tx_mgt_cb,
ieee80211_add_callback(m, ieee80211_tx_mgt_cb,