message: raja perf improvements
diff: @@ -91,7 +91,8 @@ using RAJA::statement::Segs;
  template <const int BLOCKS = MFEM_CUDA_BLOCKS, typename DBODY>
  void RajaCudaWrap1D(const int N, DBODY &&d_body)
  {
  - RAJA::forall<RAJA::cuda_exec<BLOCKS>>(RAJA::RangeSegment(0,N),d_body);
  + //true denotes asynchronous kernel
  + RAJA::forall<RAJA::cuda_exec<BLOCKS,true>>(RAJA::RangeSegment(0,N),d_body);
  }
  template <typename DBODY>
  @@ -102,7 +103,7 @@ void RajaCudaWrap2D(const int N, DBODY &&d_body,
  MFEM_VERIFY(BZ>0, "");
  const int G = (N+BZ-1)/BZ;
  RAJA::kernel<RAJA::KernelPolicy<
  - RAJA::statement::CudaKernel<
  + RAJA::statement::CudaKernelAsync<
  RAJA::statement::For<0, RAJA::cuda_block_x_direct,
  RAJA::statement::For<1, RAJA::cuda_thread_x_direct,
  RAJA::statement::For<2, RAJA::cuda_thread_y_direct,
  @@ -125,7 +126,7 @@ void RajaCudaWrap3D(const int N, DBODY &&d_body,
  {
  MFEM_VERIFY(N>0, "");
  RAJA::kernel<RAJA::KernelPolicy<
  - RAJA::statement::CudaKernel<
  + RAJA::statement::CudaKernelAsync<
  RAJA::statement::For<0, RAJA::cuda_block_x_direct,
  RAJA::statement::For<1, RAJA::cuda_thread_x_direct,
  RAJA::statement::For<2, RAJA::cuda_thread_y_direct,
  