arm64: dts: rockchip: add thermal nodes for rk3399 SoCs

This adds thermal zone and tsadc nodes to rk3399 dtsi, rk3399 thermal
data is including the cpu and gpu sensor zone node.

The thermal zone node is the node containing all the required info
for describing a thermal zone, including its cooling device bindings.
The thermal zone node must contain, apart from its own properties, one
sub-node containing trip nodes and one sub-node containing all the zone
cooling maps.

The following is the parameter is introduced:
* polling-delay:
The maximum number of milliseconds to wait between polls

* polling-delay-passive:
The maximum number of milliseconds to wait between polls when performing
passive cooling.

* trips:
A sub-node which is a container of only trip point nodes required to
describe the thermal zone.

* cooling-maps:
A sub-node which is a container of only cooling device map nodes, used to
describe the relation between trips and cooling devices.

* cooling-device:
A phandle of a cooling device with its specifier, referring to which
cooling device is used in this cooling specifier binding. In the cooling
specifier, the first cell is the minimum cooling state and the second cell
is the maximum cooling state used in this map.

Signed-off-by: Caesar Wang <wxt@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>