dt-bindings: hwmon: ibmpowernv: convert to dtschema

Convert existing binding to support validation.

The binding has been renamed to match its compatible strings, with no
further additions.

Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
Link: https://lore.kernel.org/r/20240322-hwmon_dtschema-v3-2-6697de2a8228@gmail.com


Signed-off-by: Guenter Roeck <linux@roeck-us.net>