Description of problem:
reinstall(rpm) ose with atomic-openshift-installer on an existing host(container installed) failed as etcd can not be enabled.

Version-Release number of selected component (if applicable):
atomic-openshift-utils-3.3.11-1.git.4.eac15df.el7.noarch

How reproducible:
always

Steps to Reproduce:
1. quick install an ose with container install on host openshift-197.lab.eng.nay.redhat.com.
containerized: true
roles:
    - master
    - etcd
    - node
    - storage
2. run "atomic-openshift-installer install"(with no install config file) and follow the guide

Enter hostname or IP address: openshift-197.lab.eng.nay.redhat.com(the existing host as above)
Will this host be an OpenShift Master? [y/N]: y
Will this host be RPM or Container based (rpm/container)? [rpm]: rpm


3. it comes to the step for "Gathering information from hosts"
Installed environment detected.
By default the installer only adds new nodes to an installed environment.
Do you want to (1) only add additional nodes or (2) reinstall the existing hosts potentially erasing any custom changes?: 

3. choose 2 to start reinstall.

4. it will start to install but failed

Actual results:
the reinstall fail for TASK [etcd : Enable etcd]
fatal: [openshift-197.lab.eng.nay.redhat.com]: FAILED! => {"changed": false, "failed": true, "msg": "Unable to enable service etcd: Failed to execute operation: Operation not supported\n"}

Expected results:
it should reinstall succesfully. the ideal result should be uninstall and then reinstall.

Additional info:
for the same steps,reinstall(container) successfully in an existing env(container installed).