This is a modification of erikh/netlink-remove-address PR

This is a modification of original PR by @erikh (R118)
to keep the netlink codebase more consistent and my OCD
under control :-)

Docker-DCO-1.1-Signed-off-by: Milos Gajdos <milosgajdos83@gmail.com> (github: milosgajdos83)
Added NetworkLinkDelIp() into netlink_unsupported.go

Docker-DCO-1.1-Signed-off-by: Milos Gajdos milosgajdos83@gmail.com (github: milosgajdos83)