mm-video-v4l2: vidc: venc: enable low latency mode

By default 2D-2S mode will be enabled in video hardware and
it has few hardware limitations in below usecases so enable
1D-1S mode to video hardware using low latency mode to avoid
hardware limitations

- Constant bitrate
- Byte mode slicing
- MB mode slicing with slice size more than 4096

Also enable MB mode slicing with slice size equal to 4096
if number of MBs per frame is greater than 4096 in CAVLC mode
in 2D-2S mode.

Change-Id: I1201dc8f49cc1c77c9d8ee821ccba42668146db7
2 files changed