mm-video-v4l2: venc: Add dynamic encoder settings support for 8916

To avoid DDR bus bandwidth issues on 8916 which has 1080p display panel,
it is required to set narrow search range and disable B-frames to lower bus
bandwidth access from venus sub system.

- Add support for narrow search range setting to set motion search range
- Disable B-frames, if encoding session resolution is more than 720p or wfd

Change-Id: Ie1630d8341bc9ad4f1964cdee3abb33fdde8ab0d