Un-namespace-qualify llvm_unreachable. It's a macro, so the qualification gave
no extra safety anyway.

llvm-svn: 91207
diff --git a/clang/lib/Sema/SemaLookup.cpp b/clang/lib/Sema/SemaLookup.cpp
index 7428e94..724e2fc 100644
--- a/clang/lib/Sema/SemaLookup.cpp
+++ b/clang/lib/Sema/SemaLookup.cpp
@@ -1167,7 +1167,7 @@
   }
   }
 
-  llvm::llvm_unreachable("unknown ambiguity kind");
+  llvm_unreachable("unknown ambiguity kind");
   return true;
 }