dt-bindings: serial: amlogic,meson-uart: support Amlogic A1

Introduce meson uart serial bindings for A1 SoC family.

Signed-off-by: Dmitry Rokosov <ddrokosov@sberdevices.ru>
Acked-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230705181833.16137-7-ddrokosov@sberdevices.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>