Enable nested virtualization on target hosts for kolla installer

After this patch, all target hosts will have KVM nested
virtualization enabled, so they can host VMs that can
in turn host VMs.

installer-type: kolla
deploy-scenario: os-nosdn-nofeature

Change-Id: Ie430b88319a329152f17c071a8dad2564a371932
diff --git a/playbooks/roles/configure-targethosts/tasks/main.yml b/playbooks/roles/configure-targethosts/tasks/main.yml
index 3fde5ec..3a02d5f 100644
--- a/playbooks/roles/configure-targethosts/tasks/main.yml
+++ b/playbooks/roles/configure-targethosts/tasks/main.yml
@@ -21,6 +21,7 @@
 - include: install-packages.yml
 - include: sync-time.yml
 - include: create-swap.yml
+- include: prepare-nova-kvm.yml
 - include: prepare-cinder-{{ cinder_storage_driver }}.yml
 - include: prepare-cinder-backup-{{ cinder_storage_backup_driver }}.yml