Fixed linux compilation.

git-svn-id: svn+ssh://svn.code.sf.net/p/supertuxkart/code/main/trunk@11489 178a84e3-b1eb-0310-8ba1-8eac791a3b58

src/items/item_manager.hpp

@@ -56,7 +56,7 @@ private:
      *  value is <0, it indicates that the items are not switched atm. */
     float m_switch_time;
 
-    void  ItemManager::insertItem(Item *item);
+    void  insertItem(Item *item);
 
 public:
                    ItemManager();