ARM: dts: tango4: Initial thermal support

Define the CPU temperature sensor, and critical trip point.

Commit 799d71da471c ("add temperature sensor support for tango SoC")
added the device driver.

Acked-by: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Marc Gonzalez <marc_gonzalez@sigmadesigns.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>