x86/PCI: set_pci_bus_resources_arch_default cleanups

Rename set_pci_bus_resources_arch_default to x86_pci_root_bus_res_quirks, move
the weak version from common.c to i386.c, and before calling, make sure it's a
root bus.

Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c
index f80ece5..2202b62 100644
--- a/arch/x86/pci/common.c
+++ b/arch/x86/pci/common.c
@@ -142,10 +142,6 @@
 	}
 }
 
-void __attribute__((weak)) set_pci_bus_resources_arch_default(struct pci_bus *b)
-{
-}
-
 /*
  *  Called after each bus is probed, but before its children
  *  are examined.
@@ -155,7 +151,9 @@
 {
 	struct pci_dev *dev;
 
-	set_pci_bus_resources_arch_default(b);
+	/* root bus? */
+	if (!b->parent)
+		x86_pci_root_bus_res_quirks(b);
 	pci_read_bridge_bases(b);
 	list_for_each_entry(dev, &b->devices, bus_list)
 		pcibios_fixup_device_resources(dev);