Generate identity API ref

The api-ref pom.xml and itemizedlist-service-list.xml files were
referencing api-ref-identity-v2.xml and api-ref-identity-v3.xml,
but these files don't exist. These were changed to refer to
api-ref-identity.xml since that exists.

Change-Id: I4528734497f655e47593e2299e7ac4602aebfe95