omxh264enc: Add timestamp information for buffer contain codec data
omxh264enc: Add timestamp information for buffer contain codec data

Buffer contain codec data will be sent in finsh_frame() with the
first video frame. It should have timestamp similar as the first
video frame to avoid downstream update incorrect timestamp when
merging codec data with video frame data

refs #112161
Signed-off-by: Thao Luong <ef4308e16b91b9bcf00aabc74dbe961cf8111f94@rvc.renesas.com>

renesas-rcar/gst-omx,renesas-rcar/gst-omx,renesas-rcar/gst-omx