pbsys/program_stop: Remove shutdown one-shot.

Since the program stop just schedules something, this does not need to be protected by a one-shot.

In fact, this is slightly safer because the mp_pending_exception could theoretically be overwritten by something other than SystemAbort before it gets handled by the VM. Now it will just keep scheduling the SystemAbort.

Author: laurensvalk

lib/pbio/sys/program_stop.c

@@ -16,8 +16,6 @@
 static pbio_button_flags_t stop_buttons = PBIO_BUTTON_CENTER;
 // State for button press one-shot
 static bool stop_button_pressed;
-// State for shutdown request one-shot
-static bool program_stop_on_shutdown_requested;
 
 /**
  * Request the user program to stop. For example, in MicroPython, this may raise
@@ -48,12 +46,8 @@ void pbsys_program_stop_set_buttons(pbio_button_flags_t buttons) {
 void pbsys_program_stop_poll(void) {
 
     // Cancel user application program if shutdown was requested.
-    if (program_stop_on_shutdown_requested) {
-        // Should not request stop more than once.
-        return;
-    } else if (pbsys_status_test(PBIO_PYBRICKS_STATUS_SHUTDOWN_REQUEST)) {
+    if (pbsys_status_test(PBIO_PYBRICKS_STATUS_SHUTDOWN_REQUEST)) {
         pbsys_program_stop(true);
-        program_stop_on_shutdown_requested = true;
         return;
     }