added note about unsupported ingress operator to AWS PrivateLink clusters

Author: aldiazRH

modules/osd-aws-privatelink-about.adoc

@@ -2,6 +2,6 @@
 [id="osd-aws-privatelink-about.adoc_{context}"]
 = Understanding AWS PrivateLink
 
-A {product-title} cluster can be created without any requirements on public subnets, internet gateways, or network address translation (NAT) gateways. In this configuration, Red Hat uses AWS PrivateLink to manage and monitor a cluster in order to avoid all public ingress network traffic.
+A {product-title} cluster can be created without any requirements on public subnets, internet gateways, or network address translation (NAT) gateways. In this configuration, Red Hat uses AWS PrivateLink to manage and monitor a cluster to avoid all public ingress network traffic. Without a public subnet, it is not possible to configure an application router as public. Configuring private application routers is the only option.
 
 For more information, see link:https://aws.amazon.com/privatelink/[AWS PrivateLink] on the AWS website.