ath9k: remove passive scan on 5 GHz if country IE knows better

If we have new found information about our location and the
current country regulatory domain does not have passive scan
flag requirements we should be able to actively scan now on those
channels.

Since AP functionality is not allowed where passive scan flags are
set this means if you have a world regulatory domain and you get a
country IE that allows that channel (with active scan) then we lift
the passive-scan requirement so you can then use AP mode.

Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>