[oe] [RFC] Drop wlan-ng recipes < 0.2.7

[Junqian Gordon Xu]

Are there any objection to dropping wlan-ng recipes before 0.2.7? 
wlan-ng recipes used to be maintained by Dirk, but he is not active 
anymore. wlan-ng 0.2.7 and 0.2.8 works well for tosa with current kernel.

I found only tosa, angstrom-2007-for-openmoko-versions.inc, and 
nylon-feed.bb, needs wlan-ng. I'm sure this change are safe for these, 
Are there any other affected entities that I'm not aware of?

Regards
Gordon