[PATCH] PCI Hotplug: Use before NULL check in shpchp_ctrl

More fun found with the coverity checker.
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

drivers/pci/hotplug/shpchp_ctrl.c

@@ -2163,12 +2163,14 @@ int shpchp_disable_slot (struct slot *p_slot)
 	u32 rc = 0;
 	int ret = 0;
 	unsigned int devfn;
-	struct pci_bus *pci_bus = p_slot->ctrl->pci_dev->subordinate;
+	struct pci_bus *pci_bus;
 	struct pci_func *func;
 
 	if (!p_slot->ctrl)
 		return 1;
 
+	pci_bus = p_slot->ctrl->pci_dev->subordinate;
+
 	/* Check to see if (latch closed, card present, power on) */
 	down(&p_slot->ctrl->crit_sect);