[DTensor] Remove compute_local_offset from _utils.py (#109096)
Separating internal changes with OSS changes. This PR contains removing the compute_local_offset from the OSS directory only.
This replaces https://github.com/pytorch/pytorch/pull/108965
Pull Request resolved: https://github.com/pytorch/pytorch/pull/109096
Approved by: https://github.com/wanchaol, https://github.com/fduwjj
