sys/v4l2/v4l2src_calls.c: Turns out we don't always get the frame sizes in a predefined order from lowest to highest ...

Original commit message from CVS:
* sys/v4l2/v4l2src_calls.c:
(gst_v4l2src_probe_caps_for_format_and_size), (sort_by_frame_size),
(gst_v4l2src_probe_caps_for_format):
Turns out we don't always get the frame sizes in a predefined
order from lowest to highest resolution, so let's just sort the
list by frame size once we've queried the possible resolutions
rather than assume any particular order. Fixes probed caps for
the camera in my HP2133 mini notebook and makes v4l2src default
to a decent size.