get_virtual_ips() reads every address bound to a CARP VHID -- the CARP
address and IP aliases on its VHID alike -- from
/api/interfaces/overview/export, with this node's CARP state, so the reading
says who holds each address. interfaces/vip_settings would list the same
addresses with each VHID's CARP password; it is not read.
vip_manager and keepalived are Linux mechanisms and are None here. Needs
napalm-device-types 4.10.0 (carp_virtual_ip).
netOrk #1121.
