xlimits.h for embedded targets

[Christian Iseli]

> Then maybe newlib should be "fixing" gcc's limits.h rather than the other
> way around.

I'll second that.  Some targets will probably not use newlib...

Seems to me that maybe the cleanest way would be to generate a basic
limits.h from the target description file (tm.h).  That's GCC's idea
of the target's limits anyway.  At first glance, this should not be
too hard... (famous last words, I know ;-)

What do you think?

					Christian