OCPBUGS-37364: Detail unsupported routes for the External DNS Operator

Author: dfitzmau

networking/external_dns_operator/external-dns-operator-release-notes.adoc

@@ -6,7 +6,7 @@ include::_attributes/common-attributes.adoc[]
 
 toc::[]
 
-The External DNS Operator deploys and manages `ExternalDNS` to provide name resolution for services and routes from the external DNS provider to {product-title}.
+The External DNS Operator deploys and manages `ExternalDNS` to provide name resolution for services and routes from the external DNS provider to {product-title}. The External DNS Operator is only supported on `x86_64` architecture.
 
 These release notes track the development of the External DNS Operator in {product-title}.
 

networking/external_dns_operator/nw-creating-dns-records-on-azure.adoc

@@ -8,4 +8,9 @@ toc::[]
 
 You can create DNS records on Azure by using the External DNS Operator.
 
+[IMPORTANT]
+====
+Using the External DNS Operator on an {product-title} cluster that runs in {azure-full} Government (MAG) regions is not supported. 
+====
+
 include::modules/nw-control-dns-records-public-hosted-zone-azure.adoc[leveloffset=+1]