[PATCH] x86/pci: fix xen.c build error when CONFIG_ACPI is not set

[Randy Dunlap]

From: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>

Fix build error when CONFIG_ACPI is not set/enabled:

../arch/x86/pci/xen.c: In function ‘pci_xen_init’:
../arch/x86/pci/xen.c:410:2: error: implicit declaration of function ‘acpi_noirq_set’; did you mean ‘acpi_irq_get’? [-Werror=implicit-function-declaration]
  acpi_noirq_set();

Fixes: 88e9ca161c13 ("xen/pci: Use acpi_noirq_set() helper to avoid #ifdef")
Signed-off-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Cc: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
Cc: xen-devel@xxxxxxxxxxxxxxxxxxxx
Cc: linux-pci@xxxxxxxxxxxxxxx
---
 arch/x86/pci/xen.c |    1 +
 1 file changed, 1 insertion(+)

--- linux-next-20200813.orig/arch/x86/pci/xen.c
+++ linux-next-20200813/arch/x86/pci/xen.c
@@ -26,6 +26,7 @@
 #include <asm/xen/pci.h>
 #include <asm/xen/cpuid.h>
 #include <asm/apic.h>
+#include <asm/acpi.h>
 #include <asm/i8259.h>
 
 static int xen_pcifront_enable_irq(struct pci_dev *dev)