GitLab

Summary:
Pull Request resolved: https://github.com/pytorch/audio/pull/2956

Merge utility binding

This commit updates the utility binding, so that we can use `is_module_available()`
for checking the existence of extension modules.

To ensure the existence of module, this commit migrates the binding of utility functions
to PyBind11.

Going forward, we should use TorchBind for ops that we want to support TorchScript,
otherwise default to PyBind11. (PyBind has advantage of not copying strings.)

Reviewed By: hwangjeff

Differential Revision: D42355992

fbshipit-source-id: 4c71d65b24a0882a38a80dc097d45ba72b4c4a6b