dt-bindings: gpu: mali-bifrost: Add Allwinner A523 compatible

Add a compatible for the Allwinner A523 SoC, with an integrated
ARM Mali G57 MC1 (Valhall-JM) GPU.

Signed-off-by: Mikhail Kalashnikov <iuncuim@gmail.com>
Link: https://lore.kernel.org/r/20250711035730.17507-2-iuncuim@gmail.com


Signed-off-by: Rob Herring (Arm) <robh@kernel.org>