[Tools] Update path in clang_format_utils after #60473 (#60782)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/60782
PR #60473 introduced a new folders nesting level, this change updates
clang_format_utils.py to accordingly adjust the way it sets up root
path.
Test Plan: Imported from OSS
Reviewed By: zhxchen17
Differential Revision: D29403622
Pulled By: ZolotukhinM
fbshipit-source-id: 6404271615c2d263834cf538ab0153c4d41cc5c3
Author
Mikhail Zolotukhin
