Bug 1580256

Description of problem:
Failed to build AMI because clusterid is not set

Version-Release number of the following components:
openshift-ansible-3.10.0-0.46.0.git.0.85c3afd.el7

How reproducible:
100%

Steps to Reproduce:
1. Follow document(https://github.com/openshift/openshift-ansible/tree/master/playbooks/aws) to build an AMI.
2. Set openshift_cloudprovider_kind to aws in inventory.yml as example(https://github.com/openshift/openshift-ansible/blob/master/playbooks/aws/provisioning-inventory.example.ini)
3. Execute build_ami playbook as step 1(https://github.com/openshift/openshift-ansible/tree/master/playbooks/aws#step-1):
# ansible-playbook -i inventory.yml build_ami.yml -e @provisioning_vars.yml

cat inventory.yml
...
openshift_cloudprovider_kind=aws
...

Actual results:
# ansible-playbook -i inventory.yml /usr/share/ansible/openshift-ansible/playbooks/aws/openshift-cluster/build_ami.yml -e @provisioning_vars.yml -vvv
...
TASK [openshift_sanitize_inventory : Ensure clusterid is set along with the cloudprovider] ***************************************************************************************************
task path: /usr/share/ansible/openshift-ansible/roles/openshift_sanitize_inventory/tasks/main.yml:35
Monday 21 May 2018  01:49:24 -0400 (0:00:00.019)       0:01:14.638 ************ 
fatal: [ec2-xx-xx-xx-xx.compute-1.amazonaws.com]: FAILED! => {
    "changed": false, 
    "failed": true, 
    "msg": "Ensure that the openshift_clusterid is set and that all infrastructure has the required tags.\nFor dynamic provisioning when using multiple clusters in different zones, tag each node with Key=kubernetes.io/cluster/xxxx,Value=clusterid where xxxx and clusterid are unique per cluster. In versions prior to 3.6, this was Key=KubernetesCluster,Value=clusterid.\nhttps://github.com/openshift/openshift-docs/blob/master/install_config/persistent_storage/dynamically_provisioning_pvs.adoc#available-dynamically-provisioned-plug-ins\n"
}

PLAY RECAP ***********************************************************************************************************************************************************************************
ec2-xx-xx-xx-xx.compute-1.amazonaws.com : ok=13   changed=0    unreachable=0    failed=1   
localhost                  : ok=14   changed=2    unreachable=0    failed=0   

Expected results:
AWS provisioning related playbook should ensure that the openshift_clusterid is set and that all infrastructure has the required tags.

Additional info: