Update some comments

arch/sim/src/up_simsmp.c

@@ -183,9 +183,13 @@ int up_cpundx(void)
  *   initialization of the OS, just before beginning normal multitasking,
  *   the additional CPUs would be started by calling this function.
  *
- *   Each CPU is provided the entry point to is IDLE task when started.  The
- *   OS initialization logic calls this function repeatedly until each CPU
- *   has been started.
+ *   Each CPU is provided the entry point to is IDLE task when started.  A
+ *   TCB for each CPU's IDLE task has been initialized and placed in the
+ *   CPU's g_assignedtasks[cpu] list.  Not stack has been alloced or
+ *   initialized.
+ *
+ *   The OS initialization logic calls this function repeatedly until each
+ *   CPU has been started, 1 through (CONFIG_SMP_NCPUS-1).
  *
  * Input Parameters:
  *   cpu - The index of the CPU being started.  This will be a numeric

arch/sim/src/up_simuart.c

@@ -139,7 +139,7 @@ static void *simuart_thread(void *arg)
 
       /* Check for failures (but don't do anything) */
 
-      for (; nread > 0; nread--)
+      if (nread == 1)
         {
 #ifdef CONFIG_SIM_UART_DATAPOST
           sched_lock();