[llvm] [DAG] Replace llvm::isNeutralConstant with SelectionDAG::isNeutralElement (PR #195827)

[Matt Arsenault via llvm-commits]

================
@@ -2277,6 +2277,19 @@ class SelectionDAG {
     return computeOverflowForMul(IsSigned, N0, N1) == OFK_Never;
   }
 
+  /// Returns true if \p V is a neutral element of Opc with Flags.
----------------
arsenm wrote:

Yes 

https://github.com/llvm/llvm-project/pull/195827