tu: Split pipeline struct into different types

tu: Split pipeline struct into different types

The common state code expects you to use a different struct for state in
graphics pipelines and in pipeline libraries. This means we need to
copy the approach radv uses in order to be compatible. This also allows
us to shrink the structs a bit by moving compute-only things to the
compute pipeline and library-only things to the library pipeline.

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/22301>