Push StringRefs through the metadata interface.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145934 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/AsmParser/LLParser.cpp b/lib/AsmParser/LLParser.cpp
index 1ef6910..4678269 100644
--- a/lib/AsmParser/LLParser.cpp
+++ b/lib/AsmParser/LLParser.cpp
@@ -1064,7 +1064,7 @@
       return TokError("expected metadata after comma");
 
     std::string Name = Lex.getStrVal();
-    unsigned MDK = M->getMDKindID(Name.c_str());
+    unsigned MDK = M->getMDKindID(Name);
     Lex.Lex();
 
     MDNode *Node;