arm64: dts: amlogic: add missing ethernet reset ID

Add reset external reset of the ethernet mac controller

Signed-off-by: Anand Moon <linux.amoon@gmail.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
Link: https://lore.kernel.org/r/20201020120141.298240-1-jbrunet@baylibre.com