Fixed crash in case of using -N without --reverse on the command line.

git-svn-id: svn+ssh://svn.code.sf.net/p/supertuxkart/code/main/branches/reverse_mode@10812 178a84e3-b1eb-0310-8ba1-8eac791a3b58

src/race/race_manager.cpp

@@ -55,6 +55,7 @@ RaceManager::RaceManager()
     m_minor_mode         = MINOR_MODE_NORMAL_RACE;
     m_track_number       = 0;
     m_coin_target        = 0;
+    setReverseTrack(false);
     setTrack("jungle");
     m_default_ai_list.clear();
     setNumLocalPlayers(0);