[clang] [llvm] [coroutine] Implement llvm.coro.await.suspend intrinsic (PR #79712)

[Chuanqi Xu via cfe-commits]

https://github.com/ChuanqiXu9 commented:

Thanks. This looks good to me except few nit comments.

Have you tested on a real world workloads?

https://github.com/llvm/llvm-project/pull/79712