Updating restriction section.

Author: roygara

articles/storage/elastic-san/elastic-san-connect-aks.md

@@ -35,7 +35,8 @@ The iSCSI CSI driver for Kubernetes is [licensed under the Apache 2.0 license](h
 
 ## Limitations
 
-- Dynamic allocation isn't currently supported.
+- Dynamic allocation isn't currently supported
+- Only `ReadWriteOnce` access mode is currently supported
 
 ## Get started