arm64: dts: allwinner: a64: Sort watchdog node

Nodes should be sorted by unit address. Move the watchdog node to the
correct place, so it will be next to the timer node when that is added.

Signed-off-by: Samuel Holland <samuel@sholland.org>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20210322044707.19479-4-samuel@sholland.org