mac80211: abort scan_work immediately when the device goes down

As long as no delay is required b/w channel change, scan work
is proceeding without scheduling a new work. In such case, we
can not abort scan work when the card was unplugged. This patch
completes the scanning immediately whenever the device goes down.

Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Rajkumar Manoharan <rmanoharan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
index d20046b..27af672 100644
--- a/net/mac80211/scan.c
+++ b/net/mac80211/scan.c
@@ -719,6 +719,11 @@
 	 * without scheduling a new work
 	 */
 	do {
+		if (!ieee80211_sdata_running(sdata)) {
+			aborted = true;
+			goto out_complete;
+		}
+
 		switch (local->next_scan_state) {
 		case SCAN_DECISION:
 			/* if no more bands/channels left, complete scan */