thermal: exynos: remove TMU_SUPPORT_TRIM_RELOAD flag
Replace TMU_SUPPORT_TRIM_RELOAD flag check in exynos_tmu_initialize()
by an explicit check for a SoC type (only Exynos3250, Exynos4412 and
Exynos5250 have TMU_SUPPORT_READY_STATUS flag set in their struct
exynos_tmu_init_data instances). Please note that this requires
adding separate SoC type for Exynos5420 so it doesn't get mistaken
with Exynos5250.
This is a preparation for introducing per-SoC type tmu_initialize
method.
There should be no functional changes caused by this patch.