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/CGException.cpp b/clang/lib/CodeGen/CGException.cpp
index f5b4434..eaa7610 100644
--- a/clang/lib/CodeGen/CGException.cpp
+++ b/clang/lib/CodeGen/CGException.cpp
@@ -1577,7 +1577,7 @@
     // second parameter.
     auto AI = CurFn->arg_begin();
     ++AI;
-    ParentFP = AI;
+    ParentFP = &*AI;
   }
 
   // Create llvm.localrecover calls for all captures.
@@ -1732,8 +1732,7 @@
   // __exception_info intrinsic.
   if (CGM.getTarget().getTriple().getArch() != llvm::Triple::x86) {
     // On Win64, the info is passed as the first parameter to the filter.
-    auto AI = CurFn->arg_begin();
-    SEHInfo = AI;
+    SEHInfo = &*CurFn->arg_begin();
     SEHCodeSlotStack.push_back(
         CreateMemTemp(getContext().IntTy, "__exception_code"));
   } else {