[IR] Adopt removal of PointerType::get pointee type overloads. NFC.

The overload was deprecated in 146ad71.  Switch our downstream
uses to the Context overload.

Author: ahmedbougacha

clang/lib/CodeGen/CGExpr.cpp

@@ -1761,7 +1761,8 @@ static Address EmitPointerWithAlignment(const Expr *E, LValueBaseInfo *BaseInfo,
             unsigned AS = DestPointeeType->isFunctionTy()
                               ? CGF.CGM.getDataLayout().getProgramAddressSpace()
                               : CGF.getTypes().getTargetAddressSpace(ETy);
-            llvm::Type *DestTy = llvm::PointerType::get(DestPointeeType, AS);
+            llvm::Type *DestTy =
+                llvm::PointerType::get(CGF.getLLVMContext(), AS);
 
             auto RemoveBoundsSafetyAttrs = [&] (const QualType& QT) {
               if (auto PtrTy = QT->getAs<PointerType>()) {

llvm/lib/Transforms/Scalar/ConstraintElimination.cpp

@@ -1134,7 +1134,7 @@ void State::addPointerBoundInfo(Value *PtrOp, Value *IdxOp, DomTreeNode *DTN,
     // against.
     I.first->second =
         new LoadInst(IdxOp->getType(),
-                     UndefValue::get(PointerType::get(IdxOp->getType(), 0)),
+                     UndefValue::get(PointerType::get(IdxOp->getContext(), 0)),
                      "ub", false, Align(1));
     ExtraCmps.push_back(cast<Instruction>(I.first->second));
   }