This is useful when creating virtual interfaces.
Keeps udev from mucking with things it shouldn't, since
the default MAC is never seen by udev when specified on
the cmd-line during creation.
Signed-off-by: NBen Greear <greearb@candelatech.com>
[check for feature flag in nl80211 to force drivers to set it]
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>