[tlbuild] building on Solaris 11

[Karl Berry]

    ../../doc/texlive.texi:61: Unknown command `TL:'.

1) It should not have been trying to remake the .info file, since there
an up-to-date version in the repository.  I can't say why that was
happening.

2) I think the "@TL" on that line in texlive.texi needed braces (Texinfo
macros are horrible) for your version of makeinfo.  Anyway, I just replaced
it with straight text and committed new versions.

3) Hopefully you could avoid any info rebuilding in the future by
setting MAKEINFO=false in the environment for the build.

Hope this helps,
Karl