frontends/va: ROI feature supported in encoders
What does this MR do and why?
Implemented ROI feature for VCN encoders, on all the codecs and different
generations.
It can be tested by using this example command line (it only generates 2 frames):
ffmpeg -hwaccel vaapi -vaapi_device /dev/dri/renderD128 -i ./STREAM1_720p30.y4m -vf 'format=nv12|vaapi, hwupload, addroi=64:64:128:128:-0.3', -c:v h264_vaapi -bf 0 -g 1 -vframes 2 ./STREAM1_720p30_roi.264
Signed-off-by: Ruijing Dong <ruijing.dong@amd.com>