Move fx2trt out of PyTorch core (#72499)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/72499
Pull Request resolved: https://github.com/pytorch/benchmark/pull/740
To fx2trt out of tree to remove bloatness of PyTorch core.
It's the first and major step. Next, we will move acc_tracer out of the tree and rearrange some fx passes.
Reviewed By: suo
Differential Revision: D34065866
fbshipit-source-id: c72b7ad752d0706abd9a63caeef48430e85ec56d
(cherry picked from commit 91647adbcae9cae7c55aa46f4279d42b35bc723e)