CONFIG_LDM is useless; you're stuck with it now :)

Also, the struct device_driver callbacks have never been used. The objects that are being
called 'devices' aren't really devices anyway; they're merely firmware representations of them...

Remove the unused (wrapped in #ifdef 0) functions acpi_platform_add() and acpi_platform_remove().

Remove the unused (commented out) functions acpi_add_device_fs() and acpi_remove_device_fs().