[PATCH] ppc32: Switch to KBUILD_DEFCONFIG

The following patch switches ppc32 from using arch/ppc/defconfig to
arch/ppc/configs/common_defconfig as a defconfig.  These files are supposed
to be identical, but always end up out of sync.  This also updates the
common_defconfig with current options.
Signed-off-by: Tom Rini <trini@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/ppc/Makefile

@@ -42,6 +42,9 @@ cpu-as-$(CONFIG_E500)		+= -Wa,-me500
 AFLAGS += $(cpu-as-y)
 CFLAGS += $(cpu-as-y)
 
+# Default to the common case.
+KBUILD_DEFCONFIG := common_defconfig
+
 head-y				:= arch/ppc/kernel/head.o
 head-$(CONFIG_8xx)		:= arch/ppc/kernel/head_8xx.o
 head-$(CONFIG_4xx)		:= arch/ppc/kernel/head_4xx.o