In the Streams on Openshift guide, we describe how to transition kafka node roles from dual role (controller and broker) to single role (controller or broker) and vice versa. This is done using node pools.  We should document the approach required when using AMQ Streams on RHEL.

Acceptance criteria

• The documentation has been updated to describe the process.
• The updated sections have been reviewed by QE and SMEs
• Docs ready to publish with the 2.8 release