Extend jit::load to work on flatbuffer file; Take 2 (#75256)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/75256
ghstack-source-id: 153138970
Test Plan: CI
Reviewed By: iseeyuan
Differential Revision: D35399581
fbshipit-source-id: dafe9d301009d3f70986ed92bfe06d160ab90ba0
(cherry picked from commit ccc860fd07946de5aae12bc179a0b8bbba83b997)
