dt-bindings: pinctrl: renesas: Add RZ/G2L POEG binding

Add device tree bindings for the RZ/G2L Port Output Enable for GPT (POEG).

Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20221215213206.56666-2-biju.das.jz@bp.renesas.com


Signed-off-by: Linus Walleij <linus.walleij@linaro.org>