message: fix dil_cat bug when concating empty tensors with customized shape
diff: @@ -2113,9 +2113,8 @@ at::Tensor& AtenIpexCPUDev::dil_cat_out(at::Tensor& result, at::TensorList tenso
  dim = at::legacy_cat_wrap_dim(dim, tensors);
  std::vector<dil::tensor> x;
  for (auto i =0; i< tensors.size(); i++) {
  - IPEX_CHECK(!(tensors[i].dim() == 1 && tensors[i].sizes()[0] == 0),
  - "Currently Mkldnn cat operators do not support empty tensor.");
  -
  + if(tensors[i].numel() == 0)
  + continue;
  dbl::comm::reorder_to_bf16_for_mix_prec(tensors[i], true);
  x.push_back(dbl::comm::try_gen_dil_tensor(tensors[i]));
  @@ -2141,8 +2140,8 @@ at::Tensor AtenIpexCPUDev::dil_cat(at::TensorList tensors, int64_t dim) {
  std::vector<int32_t> data_shift;
  for (auto i = 0; i < tensors.size(); i++) {
  - IPEX_CHECK(!(tensors[i].dim() == 1 && tensors[i].sizes()[0] == 0),
  - "Currently Mkldnn cat operators do not support empty tensor.");
  + if(tensors[i].numel() == 0)
  + continue;
  tensors_contiguous[i] = IS_CONTIGUOUS_ANY(tensors[i]) ? tensors[i] : tensors[i].contiguous();
  dbl::comm::reorder_to_bf16_for_mix_prec(tensors_contiguous[i], true);
  