libposix: version filter script was adding a newline
* libposix/configure.ac (AC_INIT): Use the output of
git-version-gen unmodified, os per other GNU projects...
otherwise the spurious newline added to the version number
breaks operation of the configure script (tested with
Autoconf-2.68).
* libposix/mk-tarball: Remove the filter here too, otherwise
we'll end up with two conflicting version numbers in the same
release!