message: Move #include to within #ifdef
diff: #include "../config/config.hpp"
  #include "operator.hpp"
  -#include "sparsemat.hpp"
  #ifdef MFEM_USE_MPI
  #include <mpi.h>
  #endif
  #ifdef MFEM_USE_SUITESPARSE
  +#include "sparsemat.hpp"
  #include <umfpack.h>
  #include <klu.h>
  #endif
  