message: SLEPC: set device id from MFEM device manager
diff: #ifdef MFEM_USE_SLEPC
  #include "linalg.hpp"
  -
  -#include "slepc.h"
  -
  #include "petscinternals.hpp"
  +#include "slepc.h"
  static PetscErrorCode ierr;
  +using namespace std;
  +
  namespace mfem
  {
  @@ -39,6 +39,13 @@ void MFEMInitializeSlepc(int *argc,char*** argv)
  void MFEMInitializeSlepc(int *argc,char ***argv,const char rc_file[],
  const char help[])
  {
  + if (mfem::Device::Allows(mfem::Backend::CUDA_MASK))
  + {
  + // Tell PETSc to use the same CUDA device as MFEM:
  + ierr = PetscOptionsSetValue(NULL,"-cuda_device",
  + to_string(mfem::Device::GetId()).c_str());
  + MFEM_VERIFY(!ierr,"Unable to set initial option value to PETSc");
  + }
  ierr = SlepcInitialize(argc,argv,rc_file,help);
  MFEM_VERIFY(!ierr,"Unable to initialize SLEPc");
  }
  @@ -81,7 +88,6 @@ void SlepcEigenSolver::SetOperator(const PetscParMatrix &op)
  VR = new PetscParVector(op, true, false);
  VC = new PetscParVector(op, true, false);
  -
  }
  void SlepcEigenSolver::SetOperators(const PetscParMatrix &op,
  