pan/bi: Implement sysvals

Now that it's all abstracted nicely with an implementation shared with
Midgard, this is pretty easy to get.

Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4150>
2 files changed