Cleanup the USE_MPI commands in CMakeLists.txt
Cleanup the USE_MPI commands in CMakeLists.txt

rbaghdadi/ISIR,rbaghdadi/tiramisu,rbaghdadi/COLi,rbaghdadi/tiramisu,rbaghdadi/COLi,rbaghdadi/tiramisu,rbaghdadi/tiramisu,rbaghdadi/ISIR