thermal/drivers/rcar_gen3_thermal: Add support for hardware trip points

All supported hardware except V3U is capable of generating interrupts
to the CPU when the temperature go below or above a set value. Use this
to implement support for the set_trip() feature of the thermal core on
supported hardware.

The V3U have its interrupts routed to the ECM module and therefore can
not be used to implement set_trip() as the driver can't be made aware of
when the interrupt triggers.

Each TSC is capable of tracking up-to three different temperatures while
only two are needed to implement the tracking of the thermal window.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20210804091818.2196806-2-niklas.soderlund+renesas@ragnatech.se