dt-bindings: serial: ingenic: Add support for the JZ4750/55 SoCs

These SoCs UART block are the same as JZ4725b' one, the difference is
outside of the block - it is in the clock generation unit (CGU).
The difference requires to make a quirk for early console init.

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Siarhei Volkau <lis8215@gmail.com>
Link: https://lore.kernel.org/r/20221031184041.1338129-2-lis8215@gmail.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>