Currently, mcfg completion function exists in two independent implementations doing the same thing, which is bug prone. Unify the two functions and move them into one place. Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com> Acked-by: Stephen Hemminger <stephen@networkplumber.org> Acked-by: David Marchand <david.marchand@redhat.com>