if the system doesn't have ioapic, we don't need to store entries for mptable
update

also let mp_config_acpi_gsi not call func in mpparse
so later could decouple mpparse with acpi more easily
Reported-by: Daniel Exner <dex@dragonslave.de>
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Daniel Exner <dex@dragonslave.de>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>