Use deployment_type, not openshift_deployment_type

This seems to be what's used in other places

Vagrantfile

@@ -83,7 +83,7 @@ Vagrant.configure(VAGRANTFILE_API_VERSION) do |config|
         "nodes"   => ["master", "node1", "node2"],
       }
       ansible.extra_vars = {
-        openshift_deployment_type: deployment_type,
+        deployment_type: deployment_type,
       }
       ansible.playbook = "playbooks/byo/vagrant.yml"
     end

playbooks/byo/rhel_subscribe.yml

@@ -1,10 +1,10 @@
 ---
 - hosts: all
   vars:
-    deployment_type: "{{ openshift_deployment_type }}"
+    openshift_deployment_type: "{{ deployment_type }}"
   roles:
   - role: rhel_subscribe
-    when: openshift_deployment_type == "enterprise" and
+    when: deployment_type == "enterprise" and
           ansible_distribution == "RedHat" and
           lookup('oo_option', 'rhel_skip_subscription') | default(rhsub_skip, True) |
           default('no', True) | lower in ['no', 'false']