Sort the #include lines for tools/...

Again, tools are trickier to pick the main module header for than
library source files. I've started to follow the pattern of using
LLVMContext.h when it is included as a stub for program source files.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169252 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/tools/lto/lto.cpp b/tools/lto/lto.cpp
index a7e633d..11ad532 100644
--- a/tools/lto/lto.cpp
+++ b/tools/lto/lto.cpp
@@ -13,10 +13,9 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm-c/lto.h"
-#include "llvm-c/Core.h"
-
-#include "LTOModule.h"
 #include "LTOCodeGenerator.h"
+#include "LTOModule.h"
+#include "llvm-c/Core.h"
 
 
 // Holds most recent error string.