Refactor onIpv6AddressRemoved callback in IpClient.

Use LinkPropertiesUtils#compareAddresses whenever receiving the new
LinkProperties from netlink observer, which also gives the address
update i.e. add new address or delete the old address. Based on this
update we can deprecate the onIpv6AddressRemoved callback and move
all operations on detection of address being deleted, no behavior change.

Test: atest NetworkStackIntegrationTests

Change-Id: I7f2ace221f64bf98ca93833d3c12c9c6ee4673e9