PCI: Increment max correctly in pci_scan_bridge()

This patch fixes two small issues:
 - If pci_add_new_bus() fails, max must not be incremented. Otherwise
   an incorrect value is returned from pci_scan_bridge().
 - If the bus is already present, max must be incremented. I think
   that this case should only be hit if we trigger a manual rescan of a
   CardBus bridge.

Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

drivers/pci/probe.c

@@ -852,11 +852,12 @@ int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass)
 		 * this case we only re-scan this bus. */
 		child = pci_find_bus(pci_domain_nr(bus), max+1);
 		if (!child) {
-			child = pci_add_new_bus(bus, dev, ++max);
+			child = pci_add_new_bus(bus, dev, max+1);
 			if (!child)
 				goto out;
-			pci_bus_insert_busn_res(child, max, 0xff);
+			pci_bus_insert_busn_res(child, max+1, 0xff);
 		}
+		max++;
 		buses = (buses & 0xff000000)
 		      | ((unsigned int)(child->primary)     <<  0)
 		      | ((unsigned int)(child->busn_res.start)   <<  8)