arm64: dts: rockchip: Add Edgeble NCM6A-IO 2.5G ETH

Edgeble NCM6A-IO board has 2.5Gbps Ethernet via PCI2_0.

Add support for it.

Signed-off-by: Jagan Teki <jagan@edgeble.ai>
Link: https://lore.kernel.org/r/20231125190522.87607-7-jagan@edgeble.ai


Signed-off-by: Heiko Stuebner <heiko@sntech.de>