rockchip: cru: Enable cpu info support for rk3568

Add cru structure definition in head file to support cpu_info driver.

Series-version: 2
Series-changes: 2
Format the patch header, add commit message and signature.

Signed-off-by: Anton <vao@asu-vei.ru>
Signed-off-by: Kever Yang <kever.yang@rock-chips.com>