esx: implement domainInterfaceAddresses

Implement the .domainInterfaceAddresses hypervisor API, although only
functional for the VIR_DOMAIN_INTERFACE_ADDRESSES_SRC_AGENT source.

Signed-off-by: Pino Toscano <ptoscano@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>