events: Fix a compiler warning.

Fixes #11410.

src/events/SDL_events.c

@@ -730,7 +730,7 @@ static void SDL_LogEvent(const SDL_Event *event)
         SDL_EVENT_CASE(SDL_EVENT_PEN_AXIS)
         (void)SDL_snprintf(details, sizeof(details), " (timestamp=%u windowid=%u which=%u pen_state=%u x=%g y=%g axis=%s value=%g)",
                            (uint)event->paxis.timestamp, (uint)event->paxis.windowID, (uint)event->paxis.which, (uint)event->paxis.pen_state, event->paxis.x, event->paxis.y,
-                           ((event->paxis.axis >= 0) && (event->paxis.axis < SDL_arraysize(pen_axisnames))) ? pen_axisnames[event->paxis.axis] : "[UNKNOWN]", event->paxis.value);
+                           ((((int) event->paxis.axis) >= 0) && (event->paxis.axis < SDL_arraysize(pen_axisnames))) ? pen_axisnames[event->paxis.axis] : "[UNKNOWN]", event->paxis.value);
         break;
 
         SDL_EVENT_CASE(SDL_EVENT_PEN_MOTION)