tu: Split out primtype calculation for tess

tu: Split out primtype calculation for tess

With pipeline libraries, we may not know the HW primtype if the user
passes a primtype of PATCHES because the tess shaders and input assembly
state may be in different pipelines. We need to split out the patch
control points and only determine the final primtype once everything has
been merged. In preparation for this, and for dynamic patch control
points, calculate the final primtype dynamically. We already had a
draw-time workaround for dynamic primtype we can now remove, so this
actually reduces the amount of draw-time work we have to do anyway.

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/18554>