With this patch 'make vmlinux.bin' works.  This is needed by
some embedded platforms.  Kumar already added the routines
to actually build the image in arch/powerpc/boot/Makefile.
Signed-off-by: NGeoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>