arm64: dts: freescale: tx8p-ml81: fix eqos nvmem-cells

On this SoM eqos is the primary ethernet interface, Ka-Ro fuses the
address for it in eth_mac1, eth_mac2 seems to be left unfused. In their
downstream u-boot they fetch it from eth_mac1 [1][2], by setting alias
of eqos to ethernet0, the driver then fetches the mac address based on
the alias number.

Set eqos to read from eth_mac1 instead of eth_mac2. Also set fec to
point at eth_mac2 as it may be fused later even though it is disabled
by default.

With this changed barebox is now capable of loading the correct address.

Link: https://github.com/karo-electronics/karo-tx-uboot/blob/380543278410bbf04264d80a3bfbe340b8e62439/drivers/net/dwc_eth_qos.c#L1167 [1]
Link: https://github.com/karo-electronics/karo-tx-uboot/blob/380543278410bbf04264d80a3bfbe340b8e62439/arch/arm/dts/imx8mp-karo.dtsi#L12

 [2]

Fixes: bac63d7c ("arm64: dts: freescale: add Ka-Ro Electronics tx8p-ml81 COM")
Signed-off-by: Maud Spierings <maudspierings@gocontroll.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>