pan/bi: Add scheduler data structures

pan/bi: Add scheduler data structures

To satisfy the numerous architectural scheduler constraints, quite a bit
of state is required per-tuple, per-clause, and per-block. These data
structures allow maintaining this state separate from the main IR
data structures, allowing for partial constructions and nondestructive
operations.

Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/8354>