[tlbuild] Test failing on NetBSD

[Karl Berry]

    > Can you try changing that line to, say,
    >   if (*p <= 31 || *p == '\r' || *p == '\n' || *p == '\t')
    > and see if that helps?

    It's worse, tests fail even more:

Sorry, I think I reversed the sense of the test in what I sent you. (It
is hard for me to keep straight what is happening in this simple loop.)

Anyway, I changed the code to go back to simply copying all characters,
I mean bytes, and not using any is* tests. I don't see the harm. The
output might be mangled (which is the case no matter what we do here),
but so be it. I can't imagine it's going to be a problem. Meanwhile we
are spending way too much time going down this rabbit hole. --best, karl.