ipwrapper: remove Link cli parser

Nowadays we only use the Link object creation from dictionary (in
the netlink Link gathering flow. This code was deprecated and
unused (except for some tests). It is the time to get rid of this.

Change-Id: Iecffa05d8e6d6da3df57f0eb44f37465c87f93e8
Signed-off-by: Antoni S. Puimedon <asegurap@redhat.com>
Reviewed-on: http://gerrit.ovirt.org/29727
Reviewed-by: Dan Kenigsberg <danken@redhat.com>