dt-bindings: gpu: mali-bifrost: Add compatible for RZ/G3L SoC

dt-bindings: gpu: mali-bifrost: Add compatible for RZ/G3L SoC

Add a compatible string for the Renesas RZ/G3L SoC variants that include a
Mali-G31 GPU. These variants share the same restrictions on interrupts,
clocks, and power domains as the RZ/G2L SoC, so extend the existing schema
validation accordingly.

Acked-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260320164158.487406-2-biju.das.jz@bp.renesas.com
Signed-off-by: Adrián Larumbe <adrian.larumbe@collabora.com>