Clean up ARM subtarget code by using Triple ADT.

llvm-svn: 123276
diff --git a/llvm/lib/Target/ARM/AsmParser/ARMAsmParser.cpp b/llvm/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
index efe5723..190be65 100644
--- a/llvm/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
+++ b/llvm/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
@@ -9,6 +9,7 @@
 
 #include "ARM.h"
 #include "ARMAddressingModes.h"
+#include "ARMBaseRegisterInfo.h"
 #include "ARMSubtarget.h"
 #include "llvm/MC/MCParser/MCAsmLexer.h"
 #include "llvm/MC/MCParser/MCAsmParser.h"