Fix logic on namego

Now is possible to namego to a player inside an arena, by filip.havlicked
Closes issue #2130

--HG--
branch : trunk

src/server/game/Chat/Commands/Level1.cpp

@@ -817,7 +817,7 @@ bool ChatHandler::HandleNamegoCommand(const char* args)
         if (pMap->IsBattleGroundOrArena())
         {
             // only allow if gm mode is on
-            if (!target->isGameMaster())
+            if (!_player->isGameMaster())
             {
                 PSendSysMessage(LANG_CANNOT_GO_TO_BG_GM,nameLink.c_str());
                 SetSentErrorMessage(true);