x86/PCI: Drop return value of pcibios_scan_root()

Nobody really uses the return value of pcibios_scan_root() (one place uses
it to control a printk, but the printk is not very useful).  This converts
pcibios_scan_root() to a void function.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c
index 52ad00c..600e592 100644
--- a/arch/x86/pci/common.c
+++ b/arch/x86/pci/common.c
@@ -456,7 +456,7 @@
 	dmi_check_system(pciprobe_dmi_table);
 }
 
-struct pci_bus *pcibios_scan_root(int busnum)
+void pcibios_scan_root(int busnum)
 {
 	struct pci_bus *bus;
 	struct pci_sysdata *sd;
@@ -465,7 +465,7 @@
 	sd = kzalloc(sizeof(*sd), GFP_KERNEL);
 	if (!sd) {
 		printk(KERN_ERR "PCI: OOM, skipping PCI bus %02x\n", busnum);
-		return NULL;
+		return;
 	}
 	sd->node = get_mp_bus_to_node(busnum);
 	x86_pci_root_bus_resources(busnum, &resources);
@@ -475,8 +475,6 @@
 		pci_free_resource_list(&resources);
 		kfree(sd);
 	}
-
-	return bus;
 }
 
 void __init pcibios_set_cache_line_size(void)