- return the error from cxgb_tx_common so that when an error is hit we dont
spin forever in the taskq thread
- remove unused rxsd_ref
- simplify header_offset calculation for embedded mbuf headers
- fix memory leak by making sure that mbuf header initialization took place
- disable printf's for stalled queue, don't do offload/ctrl queue restart
when tunnel queue is restarted
- add more diagnostic information about the txq state
- add facility to dump the actual contents of the hardware queue using sysctl