[patches] backport support for ubnt loco xw

This backports support for Ubiquit Nanostation XW from Chaos Calmer. The
following commits have been backported:

* http://git.openwrt.org/?p=openwrt.git;a=patch;h=e92748a8b17f386a45207316e3af7c686ed887ee
* http://git.openwrt.org/?p=openwrt.git;a=patch;h=3d217029ea89de6520e01a471b6dc31924f17327

Fixes #26.
Merge pull request #170 from freifunk-berlin/features/ubnt-nano-xw-loco

[patches] backport support for ubnt loco xw