Add explicit keywords.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48801 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/ARMInstrInfo.h b/lib/Target/ARM/ARMInstrInfo.h
index 4ce90fc..29ec8be 100644
--- a/lib/Target/ARM/ARMInstrInfo.h
+++ b/lib/Target/ARM/ARMInstrInfo.h
@@ -128,7 +128,7 @@
 class ARMInstrInfo : public TargetInstrInfoImpl {
   const ARMRegisterInfo RI;
 public:
-  ARMInstrInfo(const ARMSubtarget &STI);
+  explicit ARMInstrInfo(const ARMSubtarget &STI);
 
   /// getRegisterInfo - TargetInstrInfo is a superset of MRegister info.  As
   /// such, whenever a client has an instance of instruction info, it should