Transforms: Introduce Transforms/Utils.h rather than spreading the declarations amongst Scalar.h and IPO.h

Fixes layering - Transforms/Utils shouldn't depend on including a Scalar
or IPO header, because Scalar and IPO depend on Utils.

llvm-svn: 328717
diff --git a/llvm/lib/Transforms/Utils/LoopSimplify.cpp b/llvm/lib/Transforms/Utils/LoopSimplify.cpp
index a7c2787..59c5ad4 100644
--- a/llvm/lib/Transforms/Utils/LoopSimplify.cpp
+++ b/llvm/lib/Transforms/Utils/LoopSimplify.cpp
@@ -65,7 +65,7 @@
 #include "llvm/IR/Type.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/raw_ostream.h"
-#include "llvm/Transforms/Scalar.h"
+#include "llvm/Transforms/Utils.h"
 #include "llvm/Transforms/Utils/BasicBlockUtils.h"
 #include "llvm/Transforms/Utils/LoopUtils.h"
 using namespace llvm;