In order to meet low power requirements, a power management unit (PMU) is
designed for controlling power resources in RK3399. The RK3399 PMU is
dedicated for managing the power of the whole chip.

1. add pd node for RK3399 Soc
2. create power domain tree
3. add qos node for domain

From the DT/binds and driver can get more detail information:
The driver:
        drivers/soc/rockchip/pm_domains.c
The document:
        Documentation/devicetree/bindings/soc/rockchip/power_domain.txt

Note:
As the TRM lists many voltage domains and power domains, then this patch
adds some domains for driver. Due to some domains
(e.g. emmc, usb, core)...We can't turned off it on
bootup, or says some device driver can't handle the power domain enough.
Maybe We will add more other domains in the future or later.

Signed-off-by: Elaine Zhang <zhangqing@rock-chips.com>
Signed-off-by: Caesar Wang <wxt@rock-chips.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-rockchip@lists.infradead.org
Cc: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>