This device is a dual 5GHz device. It is recommended to manually change the
radio of the first device to the lower 5GHz channels and the second radio
to the upper 5GHz channels.

Add support for IBSS meshing. Leave target marked as BROKEN for IBSS
as stability is unknown and WiFi LEDs are not working.

Functionality was tested in the network of Freifunk Frankfurt with other
ipq40xx and ar71xx devices.

This commit adds support for the new ipq40xx target.