ARM: dts: meson8: add the xtal_32k_out pin

GPIOX_10 can generate a 32768Hz signal when enabling the "xtal_32k_out"
group with the xtal function. This is typically used as LPO clock for
the SDIO wifi chips.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://lore.kernel.org/r/20230321171213.2808460-2-martin.blumenstingl@googlemail.com


Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>