ce42e79310
- Retire long time unused (basically always unused) sys__umtx_lock() and sys__umtx_unlock() syscalls - struct umtx and their supporting definitions - UMUTEX_ERROR_CHECK flag - Retire UMTX_OP_LOCK/UMTX_OP_UNLOCK from _umtx_op() syscall __FreeBSD_version is not bumped yet because it is expected that further breakages to the umtx interface will follow up in the next days. However there will be a final bump when necessary. Sponsored by: EMC / Isilon storage division Reviewed by: jhb