[NFC] Remove obsolete simplifyOnceImpl function

The function simplifyOnce only calls simplifyOnceImpl and does nothing else.
Having this separate helper makes no sense. Removing it.

Patch by Dmitry Bakunevich!

Differential Revision: https://reviews.llvm.org/D112517
Reviewed By: mkazantsev

Author: xortator

llvm/lib/Transforms/Utils/SimplifyCFG.cpp

@@ -280,7 +280,6 @@ class SimplifyCFGOpt {
   }
 
   bool simplifyOnce(BasicBlock *BB);
-  bool simplifyOnceImpl(BasicBlock *BB);
   bool run(BasicBlock *BB);
 
   // Helper to set Resimplify and return change indication.
@@ -6680,7 +6679,7 @@ static bool removeUndefIntroducingPredecessor(BasicBlock *BB,
   return false;
 }
 
-bool SimplifyCFGOpt::simplifyOnceImpl(BasicBlock *BB) {
+bool SimplifyCFGOpt::simplifyOnce(BasicBlock *BB) {
   bool Changed = false;
 
   assert(BB && BB->getParent() && "Block not embedded in function!");
@@ -6760,12 +6759,6 @@ bool SimplifyCFGOpt::simplifyOnceImpl(BasicBlock *BB) {
   return Changed;
 }
 
-bool SimplifyCFGOpt::simplifyOnce(BasicBlock *BB) {
-  bool Changed = simplifyOnceImpl(BB);
-
-  return Changed;
-}
-
 bool SimplifyCFGOpt::run(BasicBlock *BB) {
   bool Changed = false;