Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

.. revert out a local change that I hadn't yet completely finished fleshing
out and testing.

sorry!

Add a missing endian conversion.

Add the thread id to the net80211 alq records.

This will (hopefully) aid in debugging concurrency related issues.

Implement very basic ALQ logging for net80211.

This is destined to be a lightweight and optional set of ALQ
probes for debugging events which are just impossible to debug
with printf/log (eg packet TX/RX handling; AMPDU handling.)

The probes and operations themselves will appear in subsequent
commits.