Merge pull request #64064 from alishaIBM/cpms

[MULTIARCH-3728] Docs update - Control Plane Machine Set support for IBM PowerVS

Author: bburt-rh

machine_management/control_plane_machine_management/cpmso-about.adoc

@@ -25,7 +25,7 @@ The Control Plane Machine Set Operator has the following limitations:
 
 * The Operator requires the Machine API Operator to be operational and is therefore not supported on clusters with manually provisioned machines. When installing a {product-title} cluster with manually provisioned machines for a platform that creates an active generated `ControlPlaneMachineSet` custom resource (CR), you must remove the Kubernetes manifest files that define the control plane machine set as instructed in the installation process.
 
-* Only Amazon Web Services (AWS), Google Cloud Platform (GCP), Microsoft Azure, Nutanix, and VMware vSphere clusters are supported.
+* Only Amazon Web Services (AWS), Google Cloud Platform (GCP), {ibmpowerProductName} Virtual Server, Microsoft Azure, Nutanix, and VMware vSphere clusters are supported.
 
 * Only clusters with three control plane machines are supported.