kbuild/ppc*: Remove obsolete _config support

arch/ppc/Makefile

@@ -58,10 +58,6 @@ bzImage: zImage
 $(BOOT_TARGETS): vmlinux
 	$(Q)$(MAKE) $(build)=arch/ppc/boot $@
 
-%_config: arch/ppc/configs/%_defconfig
-	rm -f .config arch/ppc/defconfig
-	cp -f arch/ppc/configs/$(@:config=defconfig) .config
-
 archclean:
 	$(Q)$(MAKE) $(clean)=arch/ppc/boot
 

arch/ppc64/Makefile

@@ -41,10 +41,6 @@ boottarget-$(CONFIG_PPC_ISERIES) := vmlinux.sminitrd vmlinux.initrd vmlinux.sm
 $(boottarget-y): vmlinux
 	$(Q)$(MAKE) $(build)=$(boot) $(boot)/$@
 
-%_config: arch/ppc64/configs/%_defconfig
-	rm -f .config arch/ppc64/defconfig
-	cp -f arch/ppc64/configs/$(@:config=defconfig) arch/ppc64/defconfig
-
 bootimage-$(CONFIG_PPC_PSERIES) := zImage
 bootimage-$(CONFIG_PPC_ISERIES) := vmlinux.sm
 BOOTIMAGE := $(bootimage-y)