zink: fix channel ordering in format-mapping

This looks like a typo. Packed vulkan formats should always map to the
inverse order of the corresponding gallium notation. Besides, it makes
no sense that unsigned and signed formats have different ordering.

Fixes: cdfb1d925f3 ("zink: add last few format maps for ARB_vertex_type_2_10_10_10_rev")
Reviewed-By: Mike Blumenkrantz <michael.blumenkrantz@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7964>
(cherry picked from commit 8bb4a76addd0f0a48585ba9a4a30d6bbc5acec80)
2 files changed