hw/arm: Add WDT to Allwinner-H3 and Orangepi-PC

This patch adds WDT to Allwinner-H3 and Orangepi-PC.
WDT is added as an overlay to the Timer module memory area.

Signed-off-by: Strahinja Jankovic <strahinja.p.jankovic@gmail.com>
Reviewed-by: Niek Linnenbank <nieklinnenbank@gmail.com>
Message-id: 20230326202256.22980-4-strahinja.p.jankovic@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>