Update operation was missing for vnf-topology-operation in
    generic-resource-api. This "update" operation is needed to
    support the "modify" Trnasport Slice use-case of CCVPN.
Issue-ID: OOM-2750
Signed-off-by: Hesam Rahimi <hesam.rahimi@huawei.com>
Change-Id: I3c36abf5d7f674abc8392b20b3c374f70bf2a520
                             unassign: POST|270000|sdncurl10|sdnc-request-header|org:onap:sdnc:northbound:generic-resource
                         vnf-topology-operation:
                             create: POST|270000|sdncurl10|sdnc-request-header|org:onap:sdnc:northbound:generic-resource
+                            update: POST|270000|sdncurl10|sdnc-request-header|org:onap:sdnc:northbound:generic-resource
                             activate: POST|270000|sdncurl10|sdnc-request-header|org:onap:sdnc:northbound:generic-resource
                             assign: POST|270000|sdncurl10|sdnc-request-header|org:onap:sdnc:northbound:generic-resource
                             changeassign: POST|270000|sdncurl10|sdnc-request-header|org:onap:sdnc:northbound:generic-resource