nir: Add new rules to optimize NOOP pack/unpack pairs

nir_load_store_vectorize_test.ssbo_load_adjacent_32_32_64_64 expectations
need to be fixed accordingly.

Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5589>
2 files changed