libbsd requires rtems version number in path?

[Gedare Bloom]

I found out just now that to 'waf configure' rtems-libbsd requires
that the installed rtems is in a path with the version number
designated somehow, e.g. ${HOME}/install/4.12. I guess this is by
design, and most of our quick start guides should provide for this,
but I don't know that I've seen this "requirement" listed anywhere. It
was a bit of a surprise.

As I had not used the version number for an install, I made a symlink
with 4.12 in the name to point to my prefix to "trick" the configure.