Add missing cooling devices for CPU thermal zones in Exynos4210 SMDKv310
board.  This allows to scale down CPU frequency (and voltage) in case of
thermal pressure.

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20200830135200.24304-20-krzk@kernel.org