soc: tegra: Add thermal reset (thermtrip) support to PMC

This adds a device tree controlled option to enable PMC-based
thermal reset in overheating situations. Thermtrip is supported on
Tegra30, Tegra114 and Tegra124. The thermal reset only works when
the thermal sensors are calibrated, so a soctherm driver is also
required.

The thermtrip event is triggered by the soctherm block, and all
soctherm sensors default to showing a temperature of zero Celsius
before they are initialized. Because of this, it is safe to initialize
thermtrip and soctherm in any order.

Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>