These are hardware configuration options which are required in
the linux/openwrt device trees for the IPQ4018/IPQ4019 devices.
Since this isn't obtained from linux upstream but instead from
openwrt, this can't go in contrib; instead it is going in
sys/dts/include/ .
Obtained from: OpenWRT
Tested:
* IPQ4019 ASUS RT-AC58U AP, initial bootstrapping
