sched: Introduce rotation_ctl

This is WALT rotation logic extracted from core_ctl to avoid
CPU isolation overhead while retaining the performance gain.

Change-Id: I912d2dabf7e32eaf9da2f30b38898d1b29ff0a53
Signed-off-by: Alexander Winkowski <dereference23@outlook.com>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>