wpa_supplicant: Save prev_sched_ssid only if needed

If the whole ssid list was scanned, don't save the prev scheduled ssid
since we are going to start from beginning. Thos avoids starting sched
scan from prev_sched_ssid after scanning the full list, in case of
adding a network to ssid during scheduled scan.

Signed-hostap: David Spinadel <david.spinadel@intel.com>

wpa_supplicant/scan.c

@@ -1124,6 +1124,10 @@ scan:
 		}
 	}
 
+	/* If there is no more ssids, start next time from the beginning */
+	if (!ssid)
+		wpa_s->prev_sched_ssid = NULL;
+
 	return 0;
 }