[numerics] remove warning due to  useless variable
[numerics] remove warning due to  useless variable

bremond/siconos,bremond/siconos,fperignon/siconos,siconos/siconos,radarsat1/siconos,siconos/siconos,radarsat1/siconos,fperignon/siconos,siconos/siconos,siconos/siconos,fperignon/siconos,radarsat1/siconos,fperignon/siconos,bremond/siconos,fperignon/siconos,radarsat1/siconos,bremond/siconos,bremond/siconos,radarsat1/siconos