PCI: support PCIe ARI capability

This patch adds support for PCI Express Alternative Routing-ID
Interpretation (ARI) capability.

The ARI capability extends the Function Number field of the PCI Express
Endpoint by reusing the Device Number which is otherwise hardwired to 0.
With ARI, an Endpoint can have up to 256 functions.

Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 0080056..7e9a1f0 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -214,6 +214,7 @@
 	unsigned int	broken_parity_status:1;	/* Device generates false positive parity */
 	unsigned int 	msi_enabled:1;
 	unsigned int	msix_enabled:1;
+	unsigned int	ari_enabled:1;	/* ARI forwarding */
 	unsigned int	is_managed:1;
 	unsigned int	is_pcie:1;
 	pci_dev_flags_t dev_flags;