arm64: dts: renesas: r9a09g011: Add watchdog node

The r9a09g011 (a.k.a. RZ/V2M) comes with two watchdog IPs,
but Linux is only allowed one.

Add a node for the watchdog allowed to Linux to the SoC
specific dtsi.

Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Link: https://lore.kernel.org/r/20221103223956.50575-3-fabrizio.castro.jz@renesas.com


Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>