In 96e0d979a7, the restriction was dropped because we don't compile a
SIMD8 program on Xe2. This change moves it to run_fs() so the
restriction will be added when compiling SIMD16 on Xe2.
Fixes: 96e0d979a7 ("intel/fs: Check fs_visitor instance before using it")
Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Caio Oliveira <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/28191>