Refactor a bunch of includes so that TargetMachine.h doesn't have to include
TargetData.h.  This should make recompiles a bit faster with my current
TargetData tinkering.

llvm-svn: 28238
diff --git a/llvm/lib/Target/TargetLowering.cpp b/llvm/lib/Target/TargetLowering.cpp
index bbe8e95..50d2dfb 100644
--- a/llvm/lib/Target/TargetLowering.cpp
+++ b/llvm/lib/Target/TargetLowering.cpp
@@ -12,6 +12,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Target/TargetLowering.h"
+#include "llvm/Target/TargetData.h"
 #include "llvm/Target/TargetMachine.h"
 #include "llvm/Target/MRegisterInfo.h"
 #include "llvm/DerivedTypes.h"