Update the compatibility matrix

modules/release-notes/ref-release-notes-compatibility-matrix.adoc

@@ -0,0 +1,35 @@
+:_content-type: REFERENCE
+[id="compatibility-matrix"]
+= Compatibility matrix
+
+The following tables list products and their versions compatible with {product-short} {product-version}:
+
+.Platform compatibility matrix
+[cols=2,%header]
+|===
+|Platform
+|Version
+
+| {ocp-brand-name}
+| {ocp-version-min}-{ocp-version}
+
+| {eks-brand-name} ({eks-short})
+| Supported for Kubernetes version {kubernetes-version}
+
+| {aks-brand-name} ({aks-short})
+| Supported for Kubernetes version {kubernetes-version}
+
+| {gcp-brand-name} ({gcp-short})
+|  Supported for Kubernetes version {kubernetes-version}
+|===
+
+.Product compatibility matrix
+[cols=2,%header]
+|===
+| Product
+| Version
+
+| Backstage
+| {product-backstage-version}
+|===
+

titles/rel-notes-rhdh/title-rhdh-release-notes.adoc

@@ -8,6 +8,9 @@ include::artifacts/attributes.adoc[]
 
 {product} ({product-short}) {product-version} is now generally available. {product-short} is a fully supported, enterprise-grade productized version of upstream Backstage v{product-backstage-version}. You can access and download the {product} application from the {company-name} https://access.redhat.com/downloads[Customer Portal] or from the https://catalog.redhat.com/search?gs&q=rhdh&searchType=containers[Ecosystem Catalog].
 
+include::modules/release-notes/ref-release-notes-compatibility-matrix.adoc[leveloffset=+1]
+
+
 include::modules/release-notes/ref-release-notes-new-features.adoc[leveloffset=+1]