PCI: replace struct pci_bus secondary/subordinate with busn_res

Replace the struct pci_bus secondary/subordinate members with the
struct resource busn_res.  Later we'll build a resource tree of these
bus numbers.

[bhelgaas: changelog]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
diff --git a/arch/alpha/kernel/pci.c b/arch/alpha/kernel/pci.c
index 1a62963..53229a4 100644
--- a/arch/alpha/kernel/pci.c
+++ b/arch/alpha/kernel/pci.c
@@ -359,7 +359,7 @@
 					hose, &resources);
 		hose->bus = bus;
 		hose->need_domain_info = need_domain_info;
-		next_busno = bus->subordinate + 1;
+		next_busno = bus->busn_res.end + 1;
 		/* Don't allow 8-bit bus number overflow inside the hose -
 		   reserve some space for bridges. */ 
 		if (next_busno > 224) {