tu: Rewrite remaining pipeline LRZ handling

tu: Rewrite remaining pipeline LRZ handling

Now that the FS-specific parts are split out, the only remaining part is
the blend state part. Use the same state that we use for dynamic
blending for static blending, eliminating the last use of the pipeline
in the LRZ code. While we're at it fix a bug where dynamic blending
didn't always disable LRZ writes (even though it only mattered with a
non-conformant debug flag because we invalidated LRZ anyway).

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25276>