[llvm] [InlineCost] Enable the cost benefit analysis for Sample PGO (PR #66457)

[Xiangyang Guo via llvm-commits]

helloguo wrote:

Do you see any perf win on benchmarks and/or real applications? If so, can you share more details? We see some perf regression on our workloads.

https://github.com/llvm/llvm-project/pull/66457