Refactor request_callback_no_python.cpp processRpc function (#47816)
Summary:
Addresses step 1 of https://github.com/pytorch/pytorch/issues/46564
Took processing logic for each case in request_callback_no_python.cpp and put it in a dedicated function.
cc: izdeby
Pull Request resolved: https://github.com/pytorch/pytorch/pull/47816
Reviewed By: izdeby
Differential Revision: D25090207
Pulled By: H-Huang
fbshipit-source-id: bfa38e38db02e077d859125739aaede90ba492e7
