platform/surface: Replace acpi_bus_get_device()

Replace acpi_bus_get_device() that is going to be dropped with
acpi_fetch_acpi_dev().

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/5805278.lOV4Wx5bFT@kreacher


Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>