panvk: Fix the hierarchy_mask selection
What does this MR do and why?
Always enable the level covering the whole FB, and disable the finest levels if we don't have enough to cover everything.
This is suboptimal for small primitives, since it might force primitives to be walked multiple times even if they don't cover the the tile being processed. On the other hand, it's hard to guess the draw pattern, so it's probably good enough for now.
Fixes a tiler OOM triggered by dEQP-VK.rasterization.primitive_size.points.point_size_10000 on Valhall.