draw/mesh: reset some user state values on mesh draws.
What does this MR do and why?
draw/mesh: reset some user state values on mesh draws.
Otherwise previous non-mesh draws and can leave things dirty.
Fixes crashes in: dEQP-VK.mesh_shader.ext.query.all_queries.triangles.reset_before.copy.no_wait.indirect_draw.32bit.no_availability.no_blocks.task_mesh.inside_rp.single_view.with_secondary after other shaders have run.
Cc: mesa-stable