[tlbuild] minimal .so dependencies for xetex

[Karl Berry]

Hi Nikola,

    xetex is still linked against expat here:
      http://anthesphoria.net/FreeBSD/TeXLive-Devel/bin-r16641/

Sorry to hear it.

    (xdvipdfmx too). Build logs are available, together with output of
    ldd(1) against all binaries (*.ldd.txt). If you need anything else,
    please let me know.

I trust Peter will follow up in due course.  If you have the wherewithal
to check anything about why the libtool-hack didn't do the right thing,
that could only help.

    Btw, xetex and xdvipdfmx are the only binaries (apart from asy) that
    happen to be linked against FreeBSD base system libz. 

I surmise they are "indirect" dependencies on freetype and/or expat
(whatever term is used in BSD-land), and that this is precisely what
should be fixed by libtool-hack.

Thanks,
Karl