efi_loader: infinite recursion notifying events

UEFI SCT uses this call sequence to determine the current TPL level inside
notification functions:

    OldTpl = BS->RaiseTPL(TPL_HIGH_LEVEL);
    BS->RestoreTPL(OldTpl);

In RestoreTPL() we trigger the notification function of queued events. If
we do not mark the event as non-queued before calling the notification
function, this results in an infinite recursive call sequence.

Mark the event as non-queued before entering the notification function.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>

lib/efi_loader/efi_boottime.c

@@ -181,10 +181,12 @@ static void efi_queue_event(struct efi_event *event, bool check_tpl)
 		/* Check TPL */
 		if (check_tpl && efi_tpl >= event->notify_tpl)
 			return;
+		event->is_queued = false;
 		EFI_CALL_VOID(event->notify_function(event,
 						     event->notify_context));
+	} else {
+		event->is_queued = false;
 	}
-	event->is_queued = false;
 }
 
 /**