Goal:

• Simplify the existing provisioning templates by dropping unnecessary code

Acceptance Criteria:

• All templates used for RHEL provisioning templates should not contain any specifics for RHEL 6 as RHEL 6 is no longer supported.
• This includes all kickstart files and snippets (e.g. kickstart_kernel_options.erb, puppet_setup.erb, kickstart_default.erb
• Also conditions like `rhel_compatible && os_major >= 7` should no longer be necessary as we'll support 7+ only.

Open questions:

• Should we also clean up related Fedora conditions? What is the old enough Fedora to drop?
• Are there any specifics like this in job templates, partition tables or webhook templates? Plugins to be checked - foreman_ansible, foreman_remote_execution, foreman_webhooks, foreman_leapp, foreman_openscap. Whilte these are not necessarily provisioning templates, the same fixes may be applied to this.