thermal: exynos: cache non_hw_trigger_levels in pdata

Cache number of non-hardware trigger levels in a new pdata field
(non_hw_trigger_levels) and convert code in exynos_tmu_initialize()
accordingly.

There should be no functional changes caused by this patch.

Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Amit Daniel Kachhap <amit.daniel@samsung.com>
Tested-by: Amit Daniel Kachhap <amit.daniel@samsung.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>