[tlbuild] tl17 trial builds

[Karl Berry]

    makeinfo: unknown option -- set

It seems the timestamp of tlbuild.texi was somehow newer than .texi.
I just committed new versions to (I hope) fix that.

For the record, as stated before, the intent is that makeinfo (and bison
and flex and autotools and ...) should never need to be run by a normal
build, that is, if no files are modified. If they are, it is either a
timestamp problem somewhere or I forgot to commit the new files. Simply
touching the offending file should let you get on with life, though
reporting it is good too, of course. --sorry/thanks, k.