Description of problem:
Since fix PR for BZ#1697236 is landed in. Master instance would be created withe the same name as machine name.

If user follow "https://github.com/openshift/installer/blob/master/docs/user/aws/install_upi.md#cleanup-machine-api-resources" to delete the pre-defined master nodes, the running master would be terminated.


Version-Release number of the following components:
4.0.0-0.nightly-2019-04-10-182914

How reproducible:
always

Steps to Reproduce:
1. follow upi-on-aws doc to set up a cluster
2. after installation, check machines name
# oc get machine -n openshift-machine-api
NAME                         INSTANCE   STATE   TYPE        REGION      ZONE         AGE
jialiu-upi2-ml7bx-master-0                      m4.xlarge   us-east-2   us-east-2a   18s
jialiu-upi2-ml7bx-master-1                      m4.xlarge   us-east-2   us-east-2b   18s
jialiu-upi2-ml7bx-master-2                      m4.xlarge   us-east-2   us-east-2c   18s
3. Check created instance name via aws cli
# aws ec2 describe-instances --filters Name=tag:kubernetes.io/cluster/jialiu-upi2-ml7bx,Values=owned | jq '.Reservations[].Instances[].Tags[] | select(.Key=="Name")'
{
  "Value": "jialiu-upi2-ml7bx-worker",
  "Key": "Name"
}
{
  "Value": "jialiu-upi2-ml7bx-master-2",
  "Key": "Name"
}
{
  "Value": "jialiu-upi2-ml7bx-master-1",
  "Key": "Name"
}
{
  "Value": "jialiu-upi2-ml7bx-worker",
  "Key": "Name"
}
{
  "Value": "jialiu-upi2-ml7bx-worker",
  "Key": "Name"
}
{
  "Value": "jialiu-upi2-ml7bx-master-0",
  "Key": "Name"
}
4. Follow https://github.com/openshift/installer/blob/master/docs/user/aws/install_upi.md#cleanup-machine-api-resources to delete the pre-defined master nodes.

Actual results:
master instances are terminated, so that cluster api become unavailable.
# oc get machines --namespace openshift-machine-api
NAME                         INSTANCE   STATE   TYPE        REGION      ZONE         AGE
jialiu-upi2-ml7bx-master-0                      m4.xlarge   us-east-2   us-east-2a   46m
jialiu-upi2-ml7bx-master-1                      m4.xlarge   us-east-2   us-east-2b   46m
jialiu-upi2-ml7bx-master-2                      m4.xlarge   us-east-2   us-east-2c   46m

# oc delete machines --all --namespace openshift-machine-api
machine.machine.openshift.io "jialiu-upi2-ml7bx-master-0" deleted
machine.machine.openshift.io "jialiu-upi2-ml7bx-master-1" deleted
machine.machine.openshift.io "jialiu-upi2-ml7bx-master-2" deleted
Unable to connect to the server: http2: server sent GOAWAY and closed the connection; LastStreamID=23, ErrCode=NO_ERROR, debug=""

#oc get csr --no-headers|grep -i pending|awk '{print $1}' | xargs oc adm certificate approve
Unable to connect to the server: dial tcp 3.14.35.218:6443: i/o timeout

Expected results:
cluster api is avaiable.

Additional info:
Please attach logs from ansible-playbook with the -vvv flag