Currently, the the version file is updated in the context of
pkg.sh release-reinstall -D "$(RPM_REQUIRES_DEVEL)"
RPM_REQUIRES_DEVEL is often filled from the current version, which in
turn is filled from the version file, so the order of events here is
unclear at best.
Add target pkg-release-update-version and make pkg-release-reinstall
depend on it to make the order explicit.
Signed-off-by: Jan Lindemann <jan@janware.com>