For GPUs using the radeon kernel driver, num_se was never
getting initialised.
Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/3939
Fixes: f2977a162a ("ac: fix min/max_good_num_cu_per_sa on gfx10.3 with disabled SEs")
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7954>