Define check_sizes_nonnegative as inline (#71640)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/71640
Moving this function into the cpp file caused a small regression in
empty_cpu's callgrind instruction count, so moving it back.
Test Plan: Imported from OSS
Reviewed By: mruberry
Differential Revision: D33712880
Pulled By: ngimel
fbshipit-source-id: 64b3cb76308da38a3f0384de69500bea6ce6a30b
(cherry picked from commit d3791bc986d12a2e995bfb65fed5c35ddf7a9ae6)
