power: reset: add Toradex Embedded Controller

power: reset: add Toradex Embedded Controller

Toradex SMARC iMX8MP and SMARC iMX95 SoM modules use a small Embedded
Controller (EC) to manage power and reset functions and related SMARC
signals.

This driver implements power-off and reboot handlers, communicating with
the EC via I2C to issue the appropriate power management commands.

During probe, the driver logs the Embedded Controller ID (unique ID for
each SMARC board supported) in hex format along with the firmware version.

Signed-off-by: Emanuele Ghidoli <emanuele.ghidoli@toradex.com>
Signed-off-by: Francesco Dolcini <francesco.dolcini@toradex.com>
Link: https://lore.kernel.org/r/20250414171455.155155-3-francesco@dolcini.it
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>