ath9k: Only remove spectral scan relay file when it was created

The relay file depends on relayfs. Trying to close this file without having
ATH9K_DEBUGFS (and therefore RELAY) activated causes build failures.
Signed-off-by: NSven Eckelmann <sven@narfation.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath/ath9k/init.c

@@ -922,7 +922,7 @@ static void ath9k_deinit_softc(struct ath_softc *sc)
 
 	ath9k_eeprom_release(sc);
 
-	if (sc->rfs_chan_spec_scan) {
+	if (config_enabled(CONFIG_ATH9K_DEBUGFS) && sc->rfs_chan_spec_scan) {
 		relay_close(sc->rfs_chan_spec_scan);
 		sc->rfs_chan_spec_scan = NULL;
 	}