x86/pci: Renaming k8-bus_64.c to amd_bus.c

The name fits better since this is code not only for K8.
Signed-off-by: NRobert Richter <robert.richter@amd.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

arch/x86/pci/Makefile_64

@@ -13,5 +13,5 @@ obj-y			+= legacy.o irq.o common.o early.o
 # mmconfig has a 64bit special
 obj-$(CONFIG_PCI_MMCONFIG) += mmconfig_64.o direct.o mmconfig-shared.o
 
-obj-y		+= k8-bus_64.o
+obj-y		+= amd_bus.o