mac80211: support remain-on-channel command

This implements the new remain-on-channel cfg80211
command in mac80211, extending the work interface.

Also change the work purge code to be able to clean
up events properly (pretending they timed out.)

Signed-off-by: Jouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/main.c b/net/mac80211/main.c
index 5fcd354..d0a14d9 100644
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -107,6 +107,9 @@
 	if (scan_chan) {
 		chan = scan_chan;
 		channel_type = NL80211_CHAN_NO_HT;
+	} else if (local->tmp_channel) {
+		chan = scan_chan = local->tmp_channel;
+		channel_type = local->tmp_channel_type;
 	} else {
 		chan = local->oper_channel;
 		channel_type = local->oper_channel_type;