This also sets ownership of /var/lib/lorax/composer/ to root:weldr to
allow missing directories to be created at runtime.
(cherry picked from commit f38f5cc168)
Normally tmpfiles.d will handle this at boot time, but if you install
lorax-composer without rebooting it was ending up with root:root
ownership instead of root:weldr
(cherry picked from commit 7adc5162fb)