[clang] [llvm] [llvm][clang] Propagate VFS through LTO to `PGOOptions` (PR #159671)

[Jan Svoboda via cfe-commits]

jansvoboda11 wrote:

(FWIW I think this https://github.com/llvm/llvm-project/pull/160188 might be a better solution.)

https://github.com/llvm/llvm-project/pull/159671