arm64: dts: renesas: r8a774b1: Add SATA controller node

Add the SATA controller node to the RZ/G2N SoC specific
dtsi.

Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Link: https://lore.kernel.org/r/1571761279-17347-3-git-send-email-fabrizio.castro@bp.renesas.com


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