thermal: exynos: Bifurcate exynos thermal common and tmu controller code

This code bifurcates exynos thermal implementation into common and sensor
specific parts. The common thermal code interacts with core thermal layer and
core cpufreq cooling parts and is independent of SOC specific driver. This
change is needed to cleanly add support for new TMU sensors.

Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Acked-by: Jonghwa Lee <jonghwa3.lee@samsung.com>
Acked-by: Eduardo Valentin <eduardo.valentin@ti.com>
Signed-off-by: Amit Daniel Kachhap <amit.daniel@samsung.com>
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>