Fixed segfault on program exit if joysticks have never been initialized.

git-svn-id: svn://svn.code.sf.net/p/stella/code/trunk@2304 8b62c5a3-ac7e-4cc8-8f21-d9a121418aba

src/emucore/EventHandler.cxx

@@ -63,6 +63,7 @@ EventHandler::EventHandler(OSystem* osystem)
     myAllowAllDirectionsFlag(false),
     myFryingFlag(false),
     mySkipMouseMotion(true),
+    myJoysticks(NULL),
     myNumJoysticks(0)
 {
   // Create the event object which will be used for this handler