Configure selinux with ansible too

[martbhell]

Right now it's only configured in the kickstarts.

We have a role already: https://github.com/CSC-IT-Center-for-Science/ansible-role-selinux

But this defaults to setting selinux to permissive/targeted.

So if we want to ensure that selinux is disabled all over the cluster, we'll need to first make sure of these on all the clusters before we enable the role in the playbooks:

• the variables are set appropriately
• role is installed