ACPI: create /sys/firmware/acpi/interrupts

See Documentation/ABI/testing/sysfs-firmware-acpi

Based-on-original-patch-by: Luming Yu <luming.yu@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 63f2e6e..cb911f3 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -115,7 +115,9 @@
 
 int acpi_register_ioapic(acpi_handle handle, u64 phys_addr, u32 gsi_base);
 int acpi_unregister_ioapic(acpi_handle handle, u32 gsi_base);
+void acpi_irq_stats_init(void);
 
+extern u32 acpi_irq_handled;
 extern int acpi_mp_config;
 
 extern struct acpi_mcfg_allocation *pci_mmcfg_config;