FEM: calculix solver, fix result mesh purging on multiple result obj.
FEM: calculix solver, fix result mesh purging on multiple result obj.

Fat-Zer/FreeCAD_sf_master,Fat-Zer/FreeCAD_sf_master,Fat-Zer/FreeCAD_sf_master,Fat-Zer/FreeCAD_sf_master,Fat-Zer/FreeCAD_sf_master