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

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

- Improve bus_autoconf tool.
- Implement simple and generic language which can
be used to describe any kind of device ID structures.
- Fix endian issues.
- Add an example format file.

Suggested by: imp @
MFC after: 14 days

- Move all USB device ID arrays into so-called sections,
sorted according to the mode which they support:
host, device or dual mode
- Add generic tool to extract these data:
tools/bus_autoconf

Discussed with: imp
Suggested by: Robert Millan <rmh@debian.org>
PR: misc/157903
MFC after: 14 days