v3dv: add v3dv_write_uniforms

Initial port of the equivalent v3d_write_uniforms, to be used by the
cmd_buffer when emitting the drawing packets.

Initially doesn't include all the quniform types, only those needed by
the initial basic vulkan tests.

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6766>
5 files changed