omxvideodec: set OMX buffer flags if GST_BUFFER_FLAG_HEADER is detected
omxvideodec: set OMX buffer flags if GST_BUFFER_FLAG_HEADER is detected

OMX for R-CarM1A requires that the OMX_BUFFERFLAG_CODECCONFIG flag
be set if the Nal unit type is SPS or PPS.

renesas-devel/gst-omx,renesas-devel/gst-omx