[Static Runtime] Add a script to auto-generate out variant dispatchers (#72602)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/72602
This change adds a script to auto-generate out variant dispatchers from `caffe2/aten/src/ATen/native/native_functions.yaml` for Static Runtime.
Test Plan: The following diff, D33373928, adds out variant dispatchers generated by this diff.
Reviewed By: mikeiovine
Differential Revision: D33373919
fbshipit-source-id: 1f6d0766c561c405a2d61d0171064f39e3d15a79
(cherry picked from commit b3a1923331808f119b65776452786278dd66769f)
