nine: remove unused pipe_viewport_state::translate[3] and scale[3]

2efabd9f5a711a7f6cd1846630244b7814bf25b3 removed them as unused.

This caused random memory overwrites (reported by Coverity).

Cc: "10.4" <mesa-stable@lists.freedesktop.org>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Reviewed-by: Axel Davy <axel.davy@ens.fr>
Signed-off-by: David Heidelberg <david@ixit.cz>