Corey Richardson reported that my idle handling cleanup
(commit fd0f979a, "mac80211: simplify idle handling")
broke ath9k_htc. The reason appears to be that it wants
to go out of idle before switching channels. To fix it,
reimplement that sequence.
Reported-by: NCorey Richardson <corey@octayn.net>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>