CodeGen: Remove implicit ilist iterator conversions, NFC

Make ilist iterator conversions explicit in clangCodeGen.  Eventually
I'll remove them everywhere.

llvm-svn: 252358
diff --git a/clang/lib/CodeGen/CodeGenFunction.cpp b/clang/lib/CodeGen/CodeGenFunction.cpp
index 8801c3b..6c08812 100644
--- a/clang/lib/CodeGen/CodeGenFunction.cpp
+++ b/clang/lib/CodeGen/CodeGenFunction.cpp
@@ -763,14 +763,14 @@
     auto AI = CurFn->arg_begin();
     if (CurFnInfo->getReturnInfo().isSRetAfterThis())
       ++AI;
-    ReturnValue = Address(AI, CurFnInfo->getReturnInfo().getIndirectAlign());
+    ReturnValue = Address(&*AI, CurFnInfo->getReturnInfo().getIndirectAlign());
   } else if (CurFnInfo->getReturnInfo().getKind() == ABIArgInfo::InAlloca &&
              !hasScalarEvaluationKind(CurFnInfo->getReturnType())) {
     // Load the sret pointer from the argument struct and return into that.
     unsigned Idx = CurFnInfo->getReturnInfo().getInAllocaFieldIndex();
     llvm::Function::arg_iterator EI = CurFn->arg_end();
     --EI;
-    llvm::Value *Addr = Builder.CreateStructGEP(nullptr, EI, Idx);
+    llvm::Value *Addr = Builder.CreateStructGEP(nullptr, &*EI, Idx);
     Addr = Builder.CreateAlignedLoad(Addr, getPointerAlign(), "agg.result");
     ReturnValue = Address(Addr, getNaturalTypeAlignment(RetTy));
   } else {