vkd3d-shader/hlsl: Support SM1 relative addressing of uniforms, version 2.
Basically !1389 (closed) but rebased, removing all the overlapping things with !1388 (merged), and relying on non-constant deref copy-prop.
Basically !1389 (closed) but rebased, removing all the overlapping things with !1388 (merged), and relying on non-constant deref copy-prop.