sourceroute: fix logging arguments

Change-Id: I63cccf460104d6492fbed751e8a7b99c5d3a4c26
Signed-off-by: Dan Kenigsberg <danken@redhat.com>
Reviewed-on: http://gerrit.ovirt.org/28042
Reviewed-by: Antoni Segura Puimedon <asegurap@redhat.com>