Clean up ARM subtarget code by using Triple ADT.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123276 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/AsmParser/ARMAsmParser.cpp b/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
index efe5723..190be65 100644
--- a/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
+++ b/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"