[clang] [Clang][Driver][SamplePGO] Enable -fsample-profile-use-profi by default (PR #146795)

[Nilanjana Basu via cfe-commits]

nilanjana87 wrote:

Heads up: I'll merge this branch tomorrow. Let me know if any of the downstream users need more time before this goes in. 

> LGTM, please give downstream users ~1w to add the opt out flag to build configs before landing this.
> 
> CC @llvm/pr-subscribers-pgo for visibility.



https://github.com/llvm/llvm-project/pull/146795