This patch adds to support the RK3368 and RK3399 SoCs.

RK3368/RK3399 is one of the Rockchip family SoCs, which is an
multi-cores ARM SoCs.

This patch adds support to boot the Trusted Firmware on RK3368/RK3399
SoCs, and adds support to boot secondary CPUs, enter/exit core
power states for all CPUs in the slow/fast clusters.

This is the initial version for rockchip SoCs.(RK3368/RK3399 and next SoCs)
* Support arm gicv2 & gicv3.
* Boot up multi-cores CPU.
* Add generic CPU helper functions.
* Support suspend/resume.
* Add system_off & system_reset implementation.
* Add delay timer platform implementation.
* Support the new porting interface for the PSCI implementation.

Change-Id: I704bb3532d65e8c70dbd99b512c5e6e440ea6f43
Signed-off-by: Tony Xie <tony.xie@rock-chips.com>
Signed-off-by: Caesar Wang <wxt@rock-chips.com>
Signed-off-by: Shengfei xu <xsf@rock-chips.com>