ARM: dts: sun8i-r40: Add thermal sensor and thermal zones

There are two sensors, sensor0 for CPU, sensor1 for GPU.

Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
Tested-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>