radv: determine the workgroup size for GS non-NGG earlier

The wavesize for VS/TES/GS is always the same, so this can be computed
earlier.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/27431>
1 file changed