In arch/ppc/boot/ld.script we need OUTPUT_ARCH(powerpc:common) for the
same reasons why we need it in vmlinux.lds.S; when we build on ppc64
box, we need to be explicit about the target.

See http://linus.bkbits.net:8080/linux-2.5/cset@1.1784.8.10 for the
corresponding fix in vmlinux.lds.S.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>