Fix coredump seen in some code paths.

git-svn-id: svn://svn.berlios.de/openocd/trunk@2723 b42882b7-edfa-0310-969c-e2dbd0fdcd60

src/helper/jim.c

@@ -2828,6 +2828,9 @@ void FreeScriptInternalRep(Jim_Interp *interp, Jim_Obj *objPtr)
     int i;
     struct ScriptObj *script = (void*) objPtr->internalRep.ptr;
 
+    if (!script)
+	    return;
+
     script->inUse--;
     if (script->inUse != 0) return;
     for (i = 0; i < script->len; i++) {