compiler: Add new Vulkan shader stages

This particular ordering makes them conveniently match
VkShaderStageFlagBits, which is a property we already take advantage
of in the previous shader stages.

Abbreviations are based on the ones used in glslangValidator.

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6479>
4 files changed