Header hygiene: remove using directive and #undef DEBUG_TYPE once we're done.

llvm-svn: 214263
diff --git a/llvm/lib/CodeGen/MachineRegionInfo.cpp b/llvm/lib/CodeGen/MachineRegionInfo.cpp
index c6b6802..5a5035e 100644
--- a/llvm/lib/CodeGen/MachineRegionInfo.cpp
+++ b/llvm/lib/CodeGen/MachineRegionInfo.cpp
@@ -4,6 +4,8 @@
 #include "llvm/ADT/Statistic.h"
 #include "llvm/Analysis/RegionInfoImpl.h"
 
+#define DEBUG_TYPE "region"
+
 using namespace llvm;
 
 STATISTIC(numMachineRegions,       "The # of machine regions");