Replaced deprecated pkg_resources.packaging with packaging module (py…

…torch#113023)

Usage of `from pkg_resources import packaging` leads to a deprecation warning:
```
DeprecationWarning: pkg_resources is deprecated as an API. See https://setuptools.pypa.io/en/latest/pkg_resources.html
```
and in strict tests where warnings are errors, this leads to CI breaks, e.g.: pytorch/vision#8092

Replacing `pkg_resources.package` with `package` as it is now a pytorch dependency:
https://github.com/pytorch/pytorch/blob/fa9045a8725214c05ae4dcec5a855820b861155e/requirements.txt#L19
Pull Request resolved: pytorch#113023
Approved by: https://github.com/Skylion007, https://github.com/malfet

torch/utils/cpp_extension.py

@@ -2335,7 +2335,8 @@ def sanitize_flags(flags):
         cuda_compile_rule = ['rule cuda_compile']
         nvcc_gendeps = ''
         # --generate-dependencies-with-compile is not supported by ROCm
-        if torch.version.cuda is not None:
+        # Nvcc flag `--generate-dependencies-with-compile` is not supported by sccache, which may increase build time.
+        if torch.version.cuda is not None and os.getenv('TORCH_EXTENSION_SKIP_NVCC_GEN_DEPENDENCIES', '0') != '1':
             cuda_compile_rule.append('  depfile = $out.d')
             cuda_compile_rule.append('  deps = gcc')
             # Note: non-system deps with nvcc are only supported