ifupdown does not provide an initscript so this recipe should not
inherit update-rc.d class. Instead, we rely on init-ifupdown recipe to
startup networking.
(From OE-Core rev: 4e6bf6ea766a0d47f96b3c4682d4f7e81a5763e7)
Signed-off-by: David Vincent <freesilicon@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>