tools/thermal: Add thermal daemon skeleton

This change provides a simple daemon skeleton. It is an example of how
to use the thermal library which wraps all the complex code related to
the netlink and transforms it into a callback oriented code.

The goal of this skeleton is to give a base brick for anyone
interested in writing its own thermal engine or as an example to rely
on to write its own thermal monitoring implementation.

In the future, it will evolve with more features and hopefully more
logic.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Tested-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Link: https://lore.kernel.org/r/20220420160933.347088-5-daniel.lezcano@linaro.org