There's no documentation for a "amlogic,meson8-rng" compatible string.
Keep the default compatible string from meson.dtsi which is
"amlogic,meson-rng" (which is also documented).

This fixes a binding check error.
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://lore.kernel.org/r/20240218111959.1811676-3-martin.blumenstingl@googlemail.comSigned-off-by: Neil Armstrong <neil.armstrong@linaro.org>