Update notes for submitted changes

* Currently we set the address mode to active-active if both ip and mac is specified in allowed address pair configuration. This causes ECMP for allowed address pair route. Set the default address mode to active-standby to address VRRP use case. Closes-Bug: #1352303 Change-Id: Ib5490301c0bfb78c36ea5373286d36f3b3147bf8