radeonsi/vcn: add support of HDR sei in HEVC encoder
What does this MR do and why?
Add HDR sei support in HEVC encoder, when the source
contains MDCV(mastering display color volume) or CLL(content
light level), when doing transcoding/encoding, these
HDR MDCV and CLL information can be transferred to hevc bitstream
as sei.
Signed-off-by: Yinjie Yao <yinjie.yao@amd.com>