No need to mix super short version of names with other structures
having full name. Let's follow a more relevant naming where each and
every attribute name is self-documenting then. (such as s/id/apic_id
etc...)
Also make CONFIG_ACPI usable through IS_ENABLED by enclosing exposed
functions with ifdef CONFIG_ACPI.
Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>