Revert D24010742: [pytorch][PR] Add callgrind collection to Timer
Test Plan: revert-hammer
Differential Revision:
D24010742 (https://github.com/pytorch/pytorch/commit/9b27e0926b9025d91c1df50bb6575a801a31f299)
Original commit changeset: df6bc765f8ef
fbshipit-source-id: 4c1edd57ea932896f7052716427059c924222501
