Simplify removeVlan by removing duplicated code.

Change-Id: If5f7f7f60796a4d22f3c945253e6235d35af5cc1
Signed-off-by: Antoni S. Puimedon <asegurap@redhat.com>
Reviewed-on: http://gerrit.ovirt.org/12017
Reviewed-by: Dan Kenigsberg <danken@redhat.com>
Tested-by: Dan Kenigsberg <danken@redhat.com>