[clang] [C++20][Modules] Do not apply `getAdjustedOffset` to file-internal byte offset. (PR #184956)

[Chuanqi Xu via cfe-commits]

https://github.com/ChuanqiXu9 approved this pull request.

Sounds good to me. But due to I don't use module map, please wait for a few days for @jansvoboda11 

https://github.com/llvm/llvm-project/pull/184956