nir/opt_vectorize_io: fix a failure when vectorizing different bit sizes

Fixes: 2514999c9c5 - nir: add nir_opt_vectorize_io, vectorizing lowered IO
Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/13085

Reviewed-by: Georg Lehmann <dadschoorse@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/34897>
1 file changed