remove caffe2/core dependency from ATen/core/jit_type.h (#22441)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/22441
This include doesn't seem to be needed. Remove it to simplify mobile build dependency.
Reviewed By: dreiss
Differential Revision: D16088224
fbshipit-source-id: f6aec21655e259726412e26a006d785912436c2a
