Install the Python 3 libselinux packages for Fedora platforms. I
think this is the right choice; Fedora is a Python-3 only distro so we
shouldn't default to installing the python2 libraries.
This has a practical effect if you're using Ansible with
ansible_python_interpreter=/usr/bin/python3 as it needs these
packages.
There is some small chance of breakage if you're using Ansible still
with Python 2, I guess. In infra I notice we bring this in with
"zuul-worker" project-config element. On balance, I think that if you
need the Python 2 packages for some reason, it should be a special
install and not part of redhat-common.
Change-Id: Ibcec0b3660d01b861838c2ae87ca43d98953ce32
a77a214339