xen/pci: Retire unnecessary #ifdef CONFIG_ACPI

As the code paths that are guarded by CONFIG_XEN_DOM0 already depend
on CONFIG_ACPI so the extra #ifdef is not required. The earlier
patch that added them in had done its job.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

arch/x86/pci/xen.c

@@ -381,7 +381,6 @@ int __init pci_xen_hvm_init(void)
 }
 
 #ifdef CONFIG_XEN_DOM0
-#ifdef CONFIG_ACPI
 static __init void xen_setup_acpi_sci(void)
 {
 	int rc;
@@ -428,7 +427,6 @@ static __init void xen_setup_acpi_sci(void)
 
 	return;
 }
-#endif
 
 int __init pci_xen_initial_domain(void)
 {
@@ -438,7 +436,6 @@ int __init pci_xen_initial_domain(void)
 	x86_msi.setup_msi_irqs = xen_initdom_setup_msi_irqs;
 	x86_msi.teardown_msi_irq = xen_teardown_msi_irq;
 #endif
-#ifdef CONFIG_ACPI
 	xen_setup_acpi_sci();
 	__acpi_register_gsi = acpi_register_gsi_xen;
 	/* Pre-allocate legacy irqs */
@@ -452,7 +449,6 @@ int __init pci_xen_initial_domain(void)
 			trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE,
 			true /* allocate IRQ */);
 	}
-#endif
 	if (0 == nr_ioapics) {
 		for (irq = 0; irq < NR_IRQS_LEGACY; irq++) {
 			pirq = xen_allocate_pirq_gsi(irq);