adding ocsp details

adding that ocsp will be supported shortly

Author: mscatyao

articles/application-gateway/mutual-authentication-overview.md

@@ -68,6 +68,10 @@ For more information on how to extract trusted client CA certificate chains, see
 
 With mutual authentication, there are additional server variables that you can use to pass information about the client certificate to the backend servers behind the Application Gateway. For more information about which server variables are available and how to use them, check out [server variables](./rewrite-http-headers-url.md#mutual-authentication-server-variables-preview).
 
+## Certificate Revocation
+
+Client certificate revocation with OCSP (Online Certificate Status Protocol) will be supported shortly. 
+
 ## Next steps
 
 After learning about mutual authentication, go to [Configure Application Gateway with mutual authentication in PowerShell](./mutual-authentication-powershell.md) to create an Application Gateway using mutual authentication.