Recognize the "default" keyword, which is documented in LangRef.html
and supported in the grammar, in the lexer.

llvm-svn: 51448
diff --git a/llvm/lib/AsmParser/LLLexer.cpp b/llvm/lib/AsmParser/LLLexer.cpp
index 37032eb..2105c7e 100644
--- a/llvm/lib/AsmParser/LLLexer.cpp
+++ b/llvm/lib/AsmParser/LLLexer.cpp
@@ -452,6 +452,7 @@
   KEYWORD("dllimport", DLLIMPORT);
   KEYWORD("dllexport", DLLEXPORT);
   KEYWORD("common", COMMON);
+  KEYWORD("default", DEFAULT);
   KEYWORD("hidden", HIDDEN);
   KEYWORD("protected", PROTECTED);
   KEYWORD("extern_weak", EXTERN_WEAK);