They're no longer ralloc'd.
Fixes: 879a569884 "nir: Switch from ralloc to malloc for NIR instructions."
Reviewed-by: Emma Anholt <emma@anholt.net>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/12884>