This patch updates libva and it's drivers to a new 2.0.0 version, which bumps the shlib version, breaks ABI and also has an API change.
The patch also simplifies the ports a little and fixes the DEBUG option when present in the ports I manage.
The multimedia/mpv and multimedia/gstreamer1-vaapi ports needed fixing to compile due to the API changes. The patches I used are taken from thee upstream repositories:
https://github.com/mpv-player/mpv/commit/2ecf240b1cd20875991a5b18efafbe799864ff7f
https://cgit.freedesktop.org/gstreamer/gstreamer-vaapi/commit/gst-libs/gst/vaapi/gstvaapiutils.c?id=777bba473e3ed1c7b8b7f7f0322892851c70dfd9
If I forgot some dependent port please report that to me so I can bump PORTREVISION there too.