[compiler-rt] [clang] [clang-tools-extra] [PGO] Reland PGO's Counter Reset and File Dumping APIs #76471 (PR #78285)

[Qiongsi Wu via cfe-commits]

qiongsiwu wrote:

Thanks for to comments/suggestions @w2yehia ! The test is modified so that

1. The profile files are generated. 
2. The test does not support Windows to avoid known limitations on Windows. 

https://github.com/llvm/llvm-project/pull/78285