[Modules] Fix potential ODR violations by sinking the DEBUG_TYPE

definition below all of the header #include lines, lib/Transforms/...
edition.

This one is tricky for two reasons. We again have a couple of passes
that define something else before the includes as well. I've sunk their
name macros with the DEBUG_TYPE.

Also, InstCombine contains headers that need DEBUG_TYPE, so now those
headers #define and #undef DEBUG_TYPE around their code, leaving them
well formed modular headers. Fixing these headers was a large motivation
for all of these changes, as "leaky" macros of this form are hard on the
modules implementation.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206844 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Transforms/Utils/LoopUnrollRuntime.cpp

@@ -21,7 +21,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-#define DEBUG_TYPE "loop-unroll"
 #include "llvm/Transforms/Utils/UnrollLoop.h"
 #include "llvm/ADT/Statistic.h"
 #include "llvm/Analysis/LoopIterator.h"
@@ -37,6 +36,8 @@
 
 using namespace llvm;
 
+#define DEBUG_TYPE "loop-unroll"
+
 STATISTIC(NumRuntimeUnrolled,
           "Number of loops unrolled with run-time trip counts");