dt-bindings: serial: renesas,rsci: Document RZ/V2H(P) and RZ/V2N SoCs

dt-bindings: serial: renesas,rsci: Document RZ/V2H(P) and RZ/V2N SoCs

Document the serial communication interface (RSCI) used on the Renesas
RZ/V2H(P) (R9A09G057) and RZ/V2N (R9A09G056) SoCs. These SoCs integrate
the same RSCI IP block as the RZ/G3E (R9A09G047), so the RZ/G3E
compatible is used as a fallback for both.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20251222162909.155279-1-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>