Make sure /etc/hostname is valid for SELinux
Make sure /etc/hostname is valid for SELinux

In the gate, it is possible for /etc/hostname to not have a valid
SELinux security conext. So, reset them to default before we update
the hostname to avoid:

  TASK: [Assign hostname]
  failed: [node1] => {"failed": true}
  msg: Command failed rc=1, out=, err=Could not set property: Access
  denied

Closes-Bug: #1568047
Change-Id: Ie30c8437b310d1ea5bc75307375c255131dfe934
Needed-By: I2ff5fbb315832b8cf07c93d0dd0cdaacd958631e

dardelean/kolla-ansible,intel-onp/kolla,coolsvap/kolla,GalenMa/kolla,GalenMa/kolla,tonyli71/kolla,stackforge/kolla,nihilifer/kolla,tonyli71/kolla,coolsvap/kolla,stackforge/kolla,mrangana/kolla,openstack/kolla,mandre/kolla,dardelean/kolla-ansible,dardelean/kolla-ansible,rahulunair/kolla,rahulunair/kolla,mandre/kolla,coolsvap/kolla,mandre/kolla,intel-onp/kolla,openstack/kolla,mrangana/kolla,nihilifer/kolla,stackforge/kolla