[tex-live] tiny warning/error about missing tlmenu.bat

[Karl Berry]

    >> open(./tlpkg/installer/tlmenu.bat) failed, not copying: No such file
    ...
    Norbert, can you please try again with
        <V> set up for portable installation

Ah, the necessary hint.

There was an explicit copy of tlmenu.bat in the portable case, in the
do_postinst_stuff function in install-tl.  I just removed it since Siep
said the file was intentionally removed.

Thanks,
k