Revert "Deprecate legacy constructor torch.Tensor() (#54414)" (#55831)

Summary:
This PR reverts https://github.com/pytorch/pytorch/pull/54414 because of https://github.com/pytorch/pytorch/issues/55780

cc ysiraichi

Pull Request resolved: https://github.com/pytorch/pytorch/pull/55831

Reviewed By: agolynski

Differential Revision: D27762264

Pulled By: heitorschueroff

fbshipit-source-id: 8079a660cc440cafb9d22aa031d36dde121e13b3

docs/source/tensors.rst

@@ -176,11 +176,6 @@ Tensor class reference
    - To create a tensor with similar type but different size as another tensor,
      use ``tensor.new_*`` creation ops.
 
-   .. warning::
-      The :class:`torch.Tensor` constructor is deprecated. Instead, consider using:
-      :func:`torch.tensor` for creating tensors from tensor-like objects (e.g. lists and tuples);
-      or :func:`torch.empty` for creating uninitialized tensors with specific sizes (e.g. int).
-
 .. autoattribute:: Tensor.T
 
 .. autosummary::

torch/csrc/utils/tensor_new.cpp

@@ -473,11 +473,6 @@ Tensor legacy_tensor_ctor(c10::DispatchKey dispatch_key, at::ScalarType scalar_t
     return legacy_sparse_tensor_ctor(dispatch_key, scalar_type, args, kwargs);
   }
 
-  TORCH_WARN_ONCE(
-      "Legacy tensor constructor is deprecated. "
-      "Use: torch.tensor(...) for creating tensors from tensor-like objects; "
-      "or torch.empty(...) for creating an uninitialized tensor with specific sizes.");
-
   ParsedArgs<2> parsed_args;
   auto r = parser.parse(args, kwargs, parsed_args);
   if (r.idx == 0) {