h264: use pixel-aspect-ratio from SPS header.
h264: use pixel-aspect-ratio from SPS header.

Propagate pixel-aspect-ratio determined by the GStreamer codecparser
from the sequence headers.

Signed-off-by: Simon Farnsworth <20871d6e2bc9386118bca8a660f80e632ec37194@onelan.co.uk>
Signed-off-by: Gwenole Beauchesne <729713629d9640cc095f1c77c692e1881f8093c4@intel.com>

GStreamer/gstreamer-vaapi,01org/iotg-lin-gfx-gstreamer-vaapi,CapOM/gstreamer-vaapi,ceyusa/gstreamer-vaapi,CapOM/gstreamer-vaapi,01org/iotg-lin-gfx-gstreamer-vaapi,gbeauchesne/gstreamer-vaapi,gbeauchesne/gstreamer-vaapi,CapOM/gstreamer-vaapi,ceyusa/gstreamer-vaapi,GStreamer/gstreamer-vaapi,01org/iotg-lin-gfx-gstreamer-vaapi,gbeauchesne/gstreamer-vaapi