arm64: dts: mediatek: mt8390-genio-700-evk: Add Grinn GenioSBC-700

arm64: dts: mediatek: mt8390-genio-700-evk: Add Grinn GenioSBC-700

Add support for Grinn GenioSBC-700. The Grinn GenioSBC-700 is a
single-board computer based on the MediaTek Genio 700 SoC. Its device
tree is split into separate SoM (.dtsi) and SBC (.dtsi) files, which are
combined in the SoC-specific .dts file.

More details about the hardware:
- https://grinn-global.com/products/grinn-geniosom-700
- https://grinn-global.com/products/grinn-genioboard-edge-ai-sbc

Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Mateusz Koza <mateusz.koza@grinn-global.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>