message: fix git apply errors in README.md
diff: @@ -39,8 +39,8 @@ Intel Extension for PyTorch is a Python package to extend official PyTorch. It i
  3. Add an new backend for Intel PyTorch Extension
  ```bash
  # Apply git patch to pytorch code
  - cd ${intel_pytorch_extension_directory}
  - git apply torch_patches/dpcpp-v1.5-rc3.patch ${pytorch_directory}
  + cd ${pytorch_directory}
  + git apply ${intel_pytorch_extension_directory}/torch_patches/dpcpp-v1.5-rc3.patch
  ```
  4. Build and install PyTorch (Refer to [PyTorch guide](https://github.com/pytorch/pytorch#install-pytorch) for more details)
  