pan/bi: Add branch constant field to IR

The offsets used for branches need some extra bits twiddled, so add a
field to the clause to indicate this is happening. This is not ambiguous
since a clause can only have a single branch.

Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5260>
2 files changed