dt-bindings: serial: fsl-linflexuart: add compatible for S32G3

Add a compatible string for the uart binding of NXP S32G3 platforms. Here
we use "s32v234-linflexuart" as fallback since the current linflexuart
driver can still work on S32G3.

Signed-off-by: Wadim Mueller <wafgo01@gmail.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20240324214329.29988-3-wafgo01@gmail.com


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