Description of problem:
Can not install RPM env when specifying openshift_image_tag parameters


Version-Release number of selected component (if applicable):
openshift-ansible master

How reproducible:
always

Steps to Reproduce:
1. Install RPM environment on rhel7 
<--snip-->
openshift_image_tag=v3.2.0.5
<--snip-->

Actual results:

TASK: [openshift_master | Install Master package] ***************************** 
failed: [openshift-142.lab.eng.nay.redhat.com] => {"changed": false, "failed": true, "rc": 0, "results": []}
msg: No Package matching 'atomic-openshift-masterv3.2.0.5' found available, installed or updated



Expected results:
Install env successfully

Additional info:
If user specified the openshift_pkg_version when installing containerized env, it will fail too.
openshift_version: "{{ openshift_pkg_version | default(openshift_image_tag) | default(openshift.common.image_tag) | default('') }}"
the 'openshift_pkg_version' have higher priority than 'openshift_image_tag'