setup_IO_APIC() doesn't know that ACPI is (later) programming the IO-APICs,
so it calls print_IO_APIC() and dumps the hardware state before the hardware is programmed.
This output is at best useless, and at worst confusing.
If this output is to appear when booting with ACPI, it should occur once -- after ACPI has
programmed the APICs.
shipped in 2.4.23
queued for post 2.6.0