[llvm] [SimplifyCFG] Avoid introducing of too many phi nodes during sinking (PR #102465)

[Nikita Popov via llvm-commits]

nikic wrote:

@dtcxzyw Could you please test this one on llvm-ci as well? Note that it's based on https://github.com/llvm/llvm-project/commit/1139dee910c45cfdd4a6066b22addef585e04032.

https://github.com/llvm/llvm-project/pull/102465