bgscan: Stop bgscan only on disassociation

Stopping bgscan on any state other than COMPLETED results
in bgscan reset (stop + start) on every rekeying operation.

Signed-hostap: Eliad Peller <eliad@wizery.com>

wpa_supplicant/wpa_supplicant.c

@@ -699,7 +699,7 @@ void wpa_supplicant_set_state(struct wpa_supplicant *wpa_s,
 #ifdef CONFIG_BGSCAN
 	if (state == WPA_COMPLETED)
 		wpa_supplicant_start_bgscan(wpa_s);
-	else
+	else if (state < WPA_ASSOCIATED)
 		wpa_supplicant_stop_bgscan(wpa_s);
 #endif /* CONFIG_BGSCAN */