camtrack: tracker_image: correct setting of tracked image position

Signed-off-by: Rhys Mainwaring <rhys.mainwaring@me.com>

Author: srmainwaring

MAVProxy/modules/mavproxy_camtrack/tracker_image.py

@@ -136,7 +136,7 @@ def process_event(self, obj):
                     TrackerPos(
                         obj.top_left_x * width,
                         obj.bot_right_x * width,
-                        obj.top_left_x * height,
+                        obj.top_left_y * height,
                         obj.bot_right_y * height,
                     )
                 )