arm64: dts: armada-3720-turris-mox: Add missing ethernet0 alias

U-Boot uses ethernet* aliases for setting MAC addresses. Therefore define
also alias for ethernet0.

Fixes: 7109d817db ("arm64: dts: marvell: add DTS for Turris Mox")
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

arch/arm64/boot/dts/marvell/armada-3720-turris-mox.dts

@@ -18,6 +18,7 @@
 
 	aliases {
 		spi0 = &spi0;
+		ethernet0 = &eth0;
 		ethernet1 = &eth1;
 		mmc0 = &sdhci0;
 		mmc1 = &sdhci1;