azure_ai: include in prereq

Author: mulander

articles/postgresql/flexible-server/generative-ai-azure-cognitive.md

@@ -17,6 +17,7 @@ Azure AI extension gives the ability to invoke the [language services](../../ai-
 
 ## Prerequisites
 
+1. [Enable and configure](generative-ai-azure-overview.md#enable-the-azure_ai-extension) the `azure_ai` extension.
 1. [Create a Language resource](https://portal.azure.com/#create/Microsoft.CognitiveServicesTextAnalytics) in the Azure portal to get your key and endpoint.  
 1. After it deploys, select **Go to resource**.
 

articles/postgresql/flexible-server/generative-ai-azure-openai.md

@@ -19,6 +19,7 @@ Invoke [Azure OpenAI embeddings](../../ai-services/openai/reference.md#embedding
 
 ## Prerequisites
 
+1. [Enable and configure](generative-ai-azure-overview.md#enable-the-azure_ai-extension) the `azure_ai` extension.
 1. Create an Open AI account and [request access to Azure OpenAI Service](https://aka.ms/oai/access).
 1. Grant Access to Azure OpenAI in the desired subscription.
 1. Grant permissions to [create Azure OpenAI resources and to deploy models](../../ai-services/openai/how-to/role-based-access-control.md).