ARM: dts: define default thermal-zones for exynos4

Trip points corresponding to the one defined in the exynos_tmu_data.c
for Exynos4 have been included.
This thermal-zones attribute is afterwards reused for Exynos4210,
Exynos4412 and Exynos5250.

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