fdt overlay support is useful for all sunxi boards, enable per default
and remove it from sunxi defconfigs.
Signed-off-by: NAndre Heider <a.heider@gmail.com>
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>
Reviewed-by: NJagan Teki <jagan@openedev.com>