[kernel] fix bug introduced in 228eca05133a8dd1c2604c2baa276ab50581cbba with the suppression of the computation of Jacobian of internal forces
[kernel] fix bug introduced in 228eca05133a8dd1c2604c2baa276ab50581cbba with the suppression of the computation of Jacobian of internal forces

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