platform/x86: classmate-laptop: Register ACPI notify handlers directly

platform/x86: classmate-laptop: Register ACPI notify handlers directly

To facilitate subsequent conversion of the driver to using struct
platform_driver instead of struct acpi_driver, make it install its ACPI
notify handlers directly instead of using struct acpi_driver .notify()
callbacks.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Thadeu Lima de Souza Cascardo <cascardo@igalia.com>
Link: https://patch.msgid.link/1856277.VLH7GnMWUR@rafael.j.wysocki
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>