[InstCombine] Remove nusw handling in ptrtoint of gep fold

Now that llvm#111144 infers gep nuw, we no longer have to repeat the
inference in this fold.

Author: nikic

llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp

@@ -2106,10 +2106,7 @@ Instruction *InstCombinerImpl::visitPtrToInt(PtrToIntInst &CI) {
         Base->getType() == Ty) {
       Value *Offset = EmitGEPOffset(GEP);
       auto *NewOp = BinaryOperator::CreateAdd(Base, Offset);
-      if (GEP->hasNoUnsignedWrap() ||
-          (GEP->hasNoUnsignedSignedWrap() &&
-           isKnownNonNegative(Offset, SQ.getWithInstruction(&CI))))
-        NewOp->setHasNoUnsignedWrap(true);
+      NewOp->setHasNoUnsignedWrap(GEP->hasNoUnsignedWrap());
       return NewOp;
     }
   }