LiveIntervalUnion is not used in RegAllocBase.

Patch by Matthias Braun!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188389 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/RegAllocBase.h

@@ -38,7 +38,7 @@
 #define LLVM_CODEGEN_REGALLOCBASE
 
 #include "llvm/ADT/OwningPtr.h"
-#include "llvm/CodeGen/LiveIntervalUnion.h"
+#include "llvm/CodeGen/LiveInterval.h"
 #include "llvm/CodeGen/RegisterClassInfo.h"
 
 namespace llvm {