Fix /etc/nova permissions
Fix /etc/nova permissions

nova-api does not start when SELinux is in enforcing mode.
A dac_override error is logged. Changing the permissions to
root.nova fixes the issue.

Bug: 1344452
Change-Id: I023c6394a6e4d9c8ee661a8403171b4975124943

openstack/tripleo-image-elements,radez/tripleo-image-elements,openstack/tripleo-image-elements,rdo-management/tripleo-image-elements,radez/tripleo-image-elements,rdo-management/tripleo-image-elements