[llvm] [PGO] Add missing target datalayout in test (PR #169520)

[via llvm-commits]

dyung wrote:

I think the problem is that at least on https://lab.llvm.org/buildbot/#/builders/190/builds/31643 the x86 backend is not built so you might need a `REQUIRES` lines.

https://github.com/llvm/llvm-project/pull/169520