v4l2codecs: h264: Properly set pic_num/frame_num
The V4L2 uAPI uses pic_num for both PicNum and ShortTermPicNum. It also doe the same for both FrameNum and LongTermFrameIdx. This change does not change the fluster score, but fixed a visual corruption noticed with some third party streams.
Attaching the stream if anyone needs to reproduce.