Reorder includes to match coding standards. Fix an issue or two exposed by that.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152978 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/ARMISelLowering.h b/lib/Target/ARM/ARMISelLowering.h
index b46abda..a71b74e 100644
--- a/lib/Target/ARM/ARMISelLowering.h
+++ b/lib/Target/ARM/ARMISelLowering.h
@@ -15,6 +15,7 @@
 #ifndef ARMISELLOWERING_H
 #define ARMISELLOWERING_H
 
+#include "ARM.h"
 #include "ARMSubtarget.h"
 #include "llvm/Target/TargetLowering.h"
 #include "llvm/Target/TargetRegisterInfo.h"