arm64: dts: broadcom: bcm2712: rpi-5: Add ethernet0 alias

arm64: dts: broadcom: bcm2712: rpi-5: Add ethernet0 alias

The RP1 ethernet controller DT node contains a local-mac-address
property to pass the MAC address from the boot loader to the kernel. The
boot loader does not fill the MAC address as the ethernet0 alias is
missing. Add it.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Andrea della Porta <andrea.porta@suse.com>
Link: https://lore.kernel.org/r/20251102111443.18206-1-laurent.pinchart@ideasonboard.com
Fixes: 43456fdfc014 ("arm64: dts: broadcom: Enable RP1 ethernet for Raspberry Pi 5")
Signed-off-by: Florian Fainelli <florian.fainelli@broadcom.com>