[llvm] [VectorCombine] Use InstSimplifyFolder to simplify instrs on creation. (PR #146350)

[Florian Hahn via llvm-commits]

fhahn wrote:

Expensive check failure was due to a code path not indication that a function is modified, should be fixed in 829f2f2448f53572d097420e0df0f62b11fa0417

https://github.com/llvm/llvm-project/pull/146350