sched/wqueue: Notifier design cleanup. The original concept used pre-allocated notification data structures. However, the notification dat must persist for an indeterminate amount of time. So the design was modified to use dynamically allocted data structures. This commit simplifies the design by removed some residual 'machinery' that is no longer needed.

sched/init/os_start.c

@@ -705,12 +705,6 @@ void os_start(void)
   net_setup();
 #endif
 
-#ifdef CONFIG_SCHED_WORKQUEUE
-  /* Initialize work queue data structures */
-
-  work_initialize();
-#endif
-
   /* The processor specific details of running the operating system
    * will be handled here.  Such things as setting up interrupt
    * service routines and starting the clock are some of the things