intel drm: Remove now superfluous sentinel element from ctl_table array

This commit comes at the tail end of a greater effort to remove the
empty elements at the end of the ctl_table arrays (sentinels) which
will reduce the overall build time size of the kernel and run time
memory bloat by ~64 bytes per sentinel (further information Link :
https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/)

Remove sentinel from oa_table

Signed-off-by: Joel Granados <j.granados@samsung.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>

Author: Joelgranados

drivers/gpu/drm/i915/i915_perf.c

@@ -4896,7 +4896,6 @@ static struct ctl_table oa_table[] = {
 	 .extra1 = SYSCTL_ZERO,
 	 .extra2 = &oa_sample_rate_hard_limit,
 	 },
-	{}
 };
 
 static u32 num_perf_groups_per_gt(struct intel_gt *gt)