sh64 and mulilibs

[DJ Delorie]

How are we supposed to configure these now?  There's nothing in the
docs about configure options, and it looks like they wouldn't work
anyway, as the t-mlib files define variables that aren't used
anywhere, and patching the t-mlib files doesn't seem to help either.

And if you have built sh64 multilibs recently, a few side questions:

* How are the C++ test results?

* Does EH work right?

* How about EH with pic/PIC?

I'm running into these questions with some older sources, and trying
to reproduce (and thus debug) them with the current sources.