ARM: dts: Adding CPU cooling binding for Exynos SoCs

Presented patch aims to move data necessary for correct CPU cooling device
configuration from exynos_tmu_data.c to device tree.

Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
Acked-by: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Kukjin Kim <kgene@kernel.org>