thermal/drivers/tegra: Add driver for Tegra30 thermal sensor

All NVIDIA Tegra30 SoCs have a two-channel on-chip sensor unit which
monitors temperature and voltage of the SoC. Sensors control CPU frequency
throttling, which is activated by hardware once preprogrammed temperature
level is breached, they also send signal to Power Management controller to
perform emergency shutdown on a critical overheat of the SoC die. Add
driver for the Tegra30 TSENSOR module, exposing it as a thermal sensor.

Tested-by: Andreas Westman Dorcsak <hedmoo@yahoo.com> # Asus TF700T
Tested-by: Maxim Schwalm <maxim.schwalm@gmail.com> # Asus TF700T
Tested-by: Svyatoslav Ryhel <clamor95@gmail.com> # Asus TF201T
Tested-by: Ihor Didenko <tailormoon@rambler.ru> # Asus TF300T
Tested-by: Ion Agorria <ion@agorria.com> # Asus TF201T
Tested-by: Matt Merhar <mattmerhar@protonmail.com> # Ouya
Tested-by: Peter Geis <pgwipeout@gmail.com> # Ouya
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20210616190417.32214-4-digetx@gmail.com