panfrost: Fix Z24 vs Z32 mixup

We don't actually support Z32_UNORM; the format we've been using as such
is in fact Z24X8 / Z24S8. Fix that and drop Z32_UNORM.

Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5069>
5 files changed