radv/rra: Dump basic ray history tokens

This only dumps the begin tokens. Tokens are written to a buffer
containing a 12 byte header at the beginning.

We use an intermediate format for the ray history tokens because the RRA
format is very inefficient.

Reviewed-by: Friedrich Vock <[email protected]>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25548>
9 files changed