xdvi figure rendering broken with gs 9.26

[Karl Berry]

Hi Paul - it was my mistake. I forgot that in TL, xdvi is a shell script
that does various things with the paths. So just running xdvi in the
build directory doesn't work; quite annoying. When I put the new binary
in the regular path, the figure showed up. Yay!

I've committed the patch (Norbert's tweaked version) to TL. Thanks!!

BTW, can you make a new xdvi release sometime before TL'20, so this
change (and anything else) is in sync?
--thanks, karl.

P.S. For the record:

    Are you sure you're using ghostscript 9.27,
    and not the current git version?

I was sure. I've never compiled, or even looked at, the git version :).
Their releases are destabilizing enough.