Remove THPWrapper (#49871)
Summary:
Remove `THPWrapper` from PyTorch C code since it is not used anymore and because we have dropped Python 2 compatibility, its usage can be replaced by capsule objects (`PyCapsule_New`, `PyCapsule_CheckExact`, `PyCapsule_GetPointer` and `PyCapsule_GetDestructor`.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/49871
Reviewed By: mruberry
Differential Revision: D25715038
Pulled By: albanD
fbshipit-source-id: cc3b6f967bbe0dc42c692adf76dff4e4b667fdd5