Update dxf.cpp
Update dxf.cpp

Fixed wrong Inch scale factor. 1/25.4 was wrongly used.
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