[CodeGen] Make CGCleanup.h include what it now uses

Also move CGCleanup.h to the top of CGCleanup.cpp to verify that
CGCleanup.h really includes what it needs.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@183632 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGCleanup.cpp b/lib/CodeGen/CGCleanup.cpp
index b41c7e0..9f693ca 100644
--- a/lib/CodeGen/CGCleanup.cpp
+++ b/lib/CodeGen/CGCleanup.cpp
@@ -17,8 +17,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "CodeGenFunction.h"
 #include "CGCleanup.h"
+#include "CodeGenFunction.h"
 
 using namespace clang;
 using namespace CodeGen;