ath5k: fix misplaced default label in sifs switch

In this switch statement, the default case does not always assign
sifs.  In practice, ah->ah_bwmode cannot take values besides the
other labels, so this is not an actual problem, but it looks odd
and smatch complains thus:

    ath5k_hw_get_default_sifs() warn: missing break? reassigning 'sifs'

Silence the warning by moving default label up a line.

Signed-off-by: Bob Copeland <me@bobcopeland.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
diff --git a/drivers/net/wireless/ath/ath5k/pcu.c b/drivers/net/wireless/ath/ath5k/pcu.c
index fc47b70..f23c851 100644
--- a/drivers/net/wireless/ath/ath5k/pcu.c
+++ b/drivers/net/wireless/ath/ath5k/pcu.c
@@ -219,8 +219,8 @@
 		sifs = AR5K_INIT_SIFS_QUARTER_RATE;
 		break;
 	case AR5K_BWMODE_DEFAULT:
-		sifs = AR5K_INIT_SIFS_DEFAULT_BG;
 	default:
+		sifs = AR5K_INIT_SIFS_DEFAULT_BG;
 		if (channel->band == NL80211_BAND_5GHZ)
 			sifs = AR5K_INIT_SIFS_DEFAULT_A;
 		break;