Add dependency on docker to openshift_docker role.

I think this is intended anytime a role uses openshift_docker.

Fixes issue where docker_version is ignored for rpm based installs. We
made the dependency in openshift_version conditional to allow use of
openshift_version without significantly impacting the system, however
nothing ever actually ran the docker role after that, resulting in
docker simply being installed via the rpm dependency on
atomic-openshift.

roles/openshift_docker/meta/main.yml

@@ -13,3 +13,5 @@ galaxy_info:
   - cloud
 dependencies:
 - role: openshift_version
+- role: openshift_docker_facts
+- role: docker