Status (v4)
===========

* Eth1 not detected, but "libphy: ag71xx_mdio: probed" shows up in boot log now like on ar71xx
* Eth0: online, correct MAC, no connectivity
* Wlan0: online, correct MAC, connectivity untested
* Boot hangs after first set of &eth1 changes (see below)

Changes
=======
* &eth1 changes in DTS based on ath79.dtsi and PR 3062
* mdio1 enabled and related phy1 entry in &eth1