PCI: Add Downstream Port Containment portdrv service type

Add the Downstream Port Containment (PCIE_PORT_SERVICE_DPC) portdrv service
type, available if the device has the DPC extended capability.

[bhelgaas: split to separate patch, changelog]
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
diff --git a/drivers/pci/pcie/portdrv.h b/drivers/pci/pcie/portdrv.h
index 63cb2ef..7d82f6d 100644
--- a/drivers/pci/pcie/portdrv.h
+++ b/drivers/pci/pcie/portdrv.h
@@ -11,7 +11,7 @@
 
 #include <linux/compiler.h>
 
-#define PCIE_PORT_DEVICE_MAXSERVICES   4
+#define PCIE_PORT_DEVICE_MAXSERVICES   5
 /*
  * According to the PCI Express Base Specification 2.0, the indices of
  * the MSI-X table entries used by port services must not exceed 31