thermal: exynos: Provide separate TMU data for Exynos4412

Up till now Exynos5250 and Exynos4412 had the same definitions for TMU
data. Following commit changes that, by introducing separate
exynos4412_default_tmu_data structure.

Since Exynos4412 was chronologically first, the corresponding name for
TMU registers and default data was renamed.

Additionally, new SOC_ARCH_EXYNOS4412 type has been defined.

Moreover, the SOC_ARCH_EXYNOS name has been changed to SOC_ARCH_EXYNOS5250.

Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Reviewed-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>