[clang] [clang-tools-extra] [llvm] [compiler-rt] [PGO][GlobalValue][LTO]In GlobalValues::getGlobalIdentifier, use semicolon as delimiter for local-linkage varibles. (PR #74008)

[Fangrui Song via llvm-commits]

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

LGTM once these changes are made.

* unused `%clangxx_pgouse=`
* profraw => proftext for the PGOProfile test
* lld-available -fuse-ld=lld and windows triple simplification for the compiler-rt test

It seems useful to wait for others' opinions as well.

https://github.com/llvm/llvm-project/pull/74008