[llvm] [SDAG] Reverse the canonicalization of isInf/isNanOrInf (PR #81404)

[Jinsong Ji via llvm-commits]

jsji wrote:

Looks like we may still get libcall with this PR. https://godbolt.org/z/W1Pq8G3ar

https://github.com/llvm/llvm-project/pull/81404