arch: Move the DUMP_ON_EXIT logic after nxtask_exit.

Otherwise we will try to dump the state of the current task, however the
exit handler has already started doing some cleanup and invalidated its
group.  Accessing the group from dumponexit will crash.

Signed-off-by: Abdelatif Guettouche <abdelatif.guettouche@espressif.com>

arch/sparc/src/common/up_exit.c

@@ -137,11 +137,6 @@ void up_exit(int status)
 
   sinfo("TCB=%p exiting\n", tcb);
 
-#ifdef CONFIG_DUMP_ON_EXIT
-  sinfo("Other tasks:\n");
-  sched_foreach(_up_dumponexit, NULL);
-#endif
-
   /* Update scheduler parameters */
 
   nxsched_suspend_scheduler(tcb);
@@ -150,6 +145,11 @@ void up_exit(int status)
 
   (void)nxtask_exit();
 
+#ifdef CONFIG_DUMP_ON_EXIT
+  sinfo("Other tasks:\n");
+  sched_foreach(_up_dumponexit, NULL);
+#endif
+
   /* Now, perform the context switch to the new ready-to-run task at the
    * head of the list.
    */