. load average calculation changed to calculate it all over every tick

instead of keeping a running total of enqueued processes
   (because somehow the load average was broken)
 . added SI_KPROC_TAB to get a copy of kernel process table from PM, for
   a top implementation
 . fixed arg to sys_nice() to make it an endpoint, not a slot number

include/minix/type.h

@@ -121,7 +121,6 @@ struct kinfo {
 
 /* Runnable processes and other load-average information. */
 struct loadinfo {
-  u16_t procs_enqueued;		/* current no. of runnable processes */
   u16_t proc_load_history[_LOAD_HISTORY];	/* history of proc_s_cur */
   u16_t proc_last_slot;
   clock_t last_clock;