PCI: Widen portdrv service type from 4 bits to 8 bits

The names of port service devices previously used one nibble to encode the
port type and another nibble to encode the service type.  We're about to
add a fifth service type, so change device names to use one *byte* to
encode the service type.

For example, a hotplug port service on a downstream bridge was previously
called "pcie24" and is now called "pcie204".  The "2" encodes the device
type (PCI_EXP_TYPE_DOWNSTREAM - 4), and the "4" (now "04") encodes the
service (PCIE_PORT_SERVICE_HP).

Based on Lukas Wunner's patch:
https://github.com/l1k/linux/commit/b688d6e4873ab082e5916b1a993bc1d38c6f4178

[bhelgaas: split to separate patch, expand changelog]
Based-on-patch-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

drivers/pci/pcie/portdrv.h

@@ -18,7 +18,7 @@
  */
 #define PCIE_PORT_MAX_MSIX_ENTRIES	32
 
-#define get_descriptor_id(type, service) (((type - 4) << 4) | service)
+#define get_descriptor_id(type, service) (((type - 4) << 8) | service)
 
 extern struct bus_type pcie_port_bus_type;
 int pcie_port_device_register(struct pci_dev *dev);

drivers/pci/pcie/portdrv_core.c

@@ -338,7 +338,7 @@ static int pcie_device_init(struct pci_dev *pdev, int service, int irq)
 	device = &pcie->device;
 	device->bus = &pcie_port_bus_type;
 	device->release = release_pcie_device;	/* callback to free pcie dev */
-	dev_set_name(device, "%s:pcie%02x",
+	dev_set_name(device, "%s:pcie%03x",
 		     pci_name(pdev),
 		     get_descriptor_id(pci_pcie_type(pdev), service));
 	device->parent = &pdev->dev;