Use include_role for conditional inclusion
Use include_role for conditional inclusion

When import_role is used with a condition, the condition is
applied to all tasks in the role. This is inefficient. If we
use include_role instead, then the role inclusion task is
skipped and none of the tasks in the role are even evaluated.

Related-bug: rhbz#1922132

Change-Id: I1b4e26fd4a46599985a989441f493a3ed39237bb

openstack/tripleo-heat-templates,openstack/tripleo-heat-templates