PCI: remove secondary/subordinate in struct pci_bus

The pci_bus secondary/subordinate members are now unused, so remove them.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

include/linux/pci.h

@@ -427,8 +427,6 @@ struct pci_bus {
 
 	unsigned char	number;		/* bus number */
 	unsigned char	primary;	/* number of primary bridge */
-	unsigned char	secondary;	/* number of secondary bridge */
-	unsigned char	subordinate;	/* max number of subordinate buses */
 	unsigned char	max_bus_speed;	/* enum pci_bus_speed */
 	unsigned char	cur_bus_speed;	/* enum pci_bus_speed */