[llvm] [BOLT] Fix test with -DCLANG_DEFAULT_PIE_ON_LINUX=OFF (PR #185047)

[Paschalis Mpeis via llvm-commits]

https://github.com/paschalis-mpeis approved this pull request.

Thanks, looks good. Note that `cxxflags` would toggle `-pie` and `-fPIE` and not necessarily `-fPIC`.

I can't reproduce your setup, but if the current patch is not resolving your issue, feel free to amend it.

https://github.com/llvm/llvm-project/pull/185047