aco: declare 8-bit/16-bit reduce operations

The 8-bit float variants are only for consistency but are unused.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Reviewed-by: Rhys Perry <pendingchaos02@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4494>
2 files changed