ath9k: simplify DFS pulse interval debug printing

Make DFS pulse interval calculation independent
from CONFIG_ATH9K_DEBUGFS.

Signed-off-by: Zefir Kurtisi <zefir.kurtisi@neratec.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath9k/dfs.c b/drivers/net/wireless/ath/ath9k/dfs.c
index e0c740d..726271c 100644
--- a/drivers/net/wireless/ath/ath9k/dfs.c
+++ b/drivers/net/wireless/ath/ath9k/dfs.c
@@ -178,14 +178,12 @@
 	pe.ts = mactime;
 	if (ath9k_postprocess_radar_event(sc, &ard, &pe)) {
 		struct dfs_pattern_detector *pd = sc->dfs_detector;
-#ifdef CONFIG_ATH9K_DEBUGFS
 		ath_dbg(common, DFS,
 			"ath9k_dfs_process_phyerr: channel=%d, ts=%llu, "
 			"width=%d, rssi=%d, delta_ts=%llu\n",
 			pe.freq, pe.ts, pe.width, pe.rssi,
-			pe.ts - sc->debug.stats.dfs_stats.last_ts);
-		sc->debug.stats.dfs_stats.last_ts = pe.ts;
-#endif
+			pe.ts - sc->dfs_prev_pulse_ts);
+		sc->dfs_prev_pulse_ts = pe.ts;
 		DFS_STAT_INC(sc, pulses_processed);
 		if (pd != NULL && pd->add_pulse(pd, &pe)) {
 			DFS_STAT_INC(sc, radar_detected);