[OpenAFS] Supported Platforms

[Jim Rees]

The macppc_nbsd support is preliminary, untested, and in fact guaranteed not
to work.  I probably shouldn't have even committed it, but I thought it
might make a good starting point for someone, and I didn't want Love's hard
work to be wasted.

The param files have several obvious problems.  They have the sys_name
defined twice, they are missing XBSD_ENV.

There is a ppc section in process.s, but it may or may not be compatible
with your assembler.

The i386_nbsd code doesn't even work, so fixing that would be a good first
step toward getting ppc_nbsd going.  It shouldn't be hard, the pieces are
all there, and i386_nbsd worked at one time in the Transarc code base.  It
just takes someone with time and enthusiasm.

And yes, this should be discussed on the -devel list.