Fix the bug of comm headers. (#98658)
`comm.hpp` is exposed to the developer under `torch/include/torch/csrc/distributed/c10d/`.
But when I use it, the following error occurs : `undefined symbol:xxx`. So I want it can expose to developer.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/98658
Approved by: https://github.com/ezyang
