dt-bindings: trivial-devices: add onnn,adt7462

dt-bindings: trivial-devices: add onnn,adt7462

The adt7462 supports monitoring and controlling up to
four PWM Fan drive outputs and eight TACH inputs measures.
The adt7462 supports reading a single on chip temperature
sensor and three remote temperature sensors. There are up
to 13 voltage monitoring inputs.

Add device tree bindings for the adt7462 device.

Signed-off-by: Chanh Nguyen <chanh@os.amperecomputing.com>
Link: https://lore.kernel.org/r/20240923093800.892949-1-chanh@os.amperecomputing.com
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>