thermal: exynos: remove TMU_SUPPORT_READY_STATUS flag
Replace TMU_SUPPORT_READY_STATUS flag check in
exynos_tmu_initialize() by an explicit check for a SoC type
(all SoC types except Exynos5440 have TMU_SUPPORT_READY_STATUS
flag set in their struct exynos_tmu_init_data instances).
This is a preparation for introducing per-SoC type tmu_initialize
method.
There should be no functional changes caused by this patch.