ath9k: debug: fix spelling mistake "WATHDOG" -> "WATCHDOG"

Trivial fix to spelling mistake in PR_IS message text.
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NKalle Valo <kvalo@codeaurora.org>

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

@@ -538,7 +538,7 @@ static int read_file_interrupt(struct seq_file *file, void *data)
 	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
 		PR_IS("RXLP", rxlp);
 		PR_IS("RXHP", rxhp);
-		PR_IS("WATHDOG", bb_watchdog);
+		PR_IS("WATCHDOG", bb_watchdog);
 	} else {
 		PR_IS("RX", rxok);
 	}