zink: format test

Inspired by !7964 (merged) and the discussion on !7925 (closed), I wanted to see if I could somehow use vk_format_to_pipe_format to validate zink_format.c, and it turns out that kinda works.

This moves code that depends on zink_screen.h to zink_screen.c, and turns the code in zink_format.c into pure 1:1 format mapping, which means that anything that comes out as supported from zink_pipe_format_to_vk_format should translate back to the same format using vk_format_to_pipe_format.

This helps making sure that we map formats correctly.

In the end, we can even add some missing formats.