Scale top-left coordinates in display-monitor-attributes-list

When using multiple monitors, and HiDPI, the top-left coordinates of
the monitors need to be adjusted, not just the width and height
(Bug#31223).

* xfns.c (Fx_display_monitor_attributes_list): Scale top-left
coordinates.

src/xfns.c

@@ -5089,6 +5089,8 @@ Internal use only, use `display-monitor-attributes-list' instead.  */)
 #elif defined HAVE_GTK3
       scale = gdk_screen_get_monitor_scale_factor (gscreen, i);
 #endif
+      rec.x *= scale;
+      rec.y *= scale;
       rec.width *= scale;
       rec.height *= scale;
       work.x *= scale;