[llvm] [Coroutines] [NFCI] Don't search the DILocalVariable for __promise when constructing the debug varaible for __coro_frame (PR #105626)

[Chuanqi Xu via llvm-commits]

ChuanqiXu9 wrote:

I am going to land this since I feel this change is innocent.

https://github.com/llvm/llvm-project/pull/105626