machine generated documentation for cgen ports

[Doug Evans]

There's still a TON of work to be done before the documentation
is usable to more than just the maintainers of the port,
and what's there now may only be of MARGINAL use to port maintainers.
If one doesn't have access to a real reference manual and one wants to look
at the layout of a particular instruction, what's there now is potentially
useful.  One obviously has to keep in mind that what's there isn't
authoritative.

Anyways I'm at a needed stopping point, so fyi ...

If you check the bottom of the cgen home page http://sources.redhat.com/cgen/
you'll see links to documentation generated from the cpu files.

Feedback is certainly welcome.