Revert "sched/debug: Fix sd->*_idx limit range avoiding overflow"

This reverts commit 86c64334221d525614cb0ffdd2204987a7e51bd9.
Revert "sched/debug: Limit sd->*_idx range on sysctl"

This reverts commit df7f3080152ee1f5d64d6d2fef05d3cad42cae72.