thermal: core: Connect the threshold with the core

Initialize, de-initialize and handle the threshold in the same place
than the trip points.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://patch.msgid.link/20240923100005.2532430-3-daniel.lezcano@linaro.org


[ rjw: Subject edit ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>