mac80211: fix scan state machine

when we run high bandwidth UDP traffic and we trigger a scan, the scan
state machine seems to be looping in SUSPEND->RESUME->DECISION->SUSPEND
and SET_CHANNEL seems to be never called as 'tx_empty' is never true
while running UDP traffic. fix this by settting SET_CHANNEL state when
we get into RESUME state.

Cc: Leela Kella <[e-mail]>
Signed-off-by: Mohammed Shafi Shajakhan <[e-mail]>
Signed-off-by: John W. Linville <[e-mail]>

net/mac80211/scan.c

···
 	local->leave_oper_channel_time = jiffies;
 
 	/* advance to the next channel to be scanned */
-	local->next_scan_state = SCAN_DECISION;
+	local->next_scan_state = SCAN_SET_CHANNEL;
 }
 
 void ieee80211_scan_work(struct work_struct *work)