Revert "mm: simplify find_vma_prev"

This reverts commit 85e48b430f2808fd4dc0d2ee2173fb4331506b5c.
Disable some options
Revert "kernel:sched: LOAD_FREQ (4*HZ+61) avoids loadavg Moire"

This reverts commit f952d6e631a77268be7595e70db934eeb97e795c.
Revert "sched/rt: code cleanup, remove a redundant function call"

This reverts commit ac1dc15ee137facf59050c478671a0fe208c167d.