x86, io_apic: Convert setup_ioapic_entry to function pointer

This pointer is changed to a different function when IRQ
remapping is enabled.

Signed-off-by: Joerg Roedel <joro@8bytes.org>
Acked-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

arch/x86/kernel/x86_init.c

@@ -127,4 +127,5 @@ struct x86_io_apic_ops x86_io_apic_ops = {
 	.disable		= native_disable_io_apic,
 	.print_entries		= native_io_apic_print_entries,
 	.set_affinity		= native_ioapic_set_affinity,
+	.setup_entry		= native_setup_ioapic_entry,
 };