Remove another 'using namespace llvm' from the

RecursiveSymbolVisitor.h header

This should fix the modules build
(http://lab.llvm.org:8011/builders/clang-x86_64-linux-selfhost-modules-2/).

llvm-svn: 307908

clang/include/clang/Tooling/Refactoring/RecursiveSymbolVisitor.h

@@ -20,8 +20,6 @@
 #include "clang/AST/RecursiveASTVisitor.h"
 #include "clang/Lex/Lexer.h"
 
-using namespace llvm;
-
 namespace clang {
 namespace tooling {