enhance h264 encode vui header setting
enhance h264 encode vui header setting

it's from h264 spec, add fix bit rate, low delay , mv over boundary flags

Signed-off-by: xfengcarl <7171cee3b9c45368cbde9fe32bc1bbad98e98a6b@intel.com>

01org/libva-cros,01org/libva-cros,01org/libva-cros