dt-bindings: clock: meson: add A1 PLL clock controller bindings

Add the documentation and dt bindings for Amlogic A1 PLL clock
controller.
Also include new A1 clock controller dt bindings to MAINTAINERS.

Signed-off-by: Jian Hu <jian.hu@amlogic.com>
Signed-off-by: Dmitry Rokosov <ddrokosov@sberdevices.ru>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Link: https://lore.kernel.org/r/20230523135351.19133-4-ddrokosov@sberdevices.ru


Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>