mac80211: Fix sparse warning for ssid_len on ieee80211_sta_config_auth()

net/mac80211/mlme.c:2079:28: warning: symbol 'ssid_len' shadows an earlier one
net/mac80211/mlme.c:2022:12: originally declared here

ssid_len is already being declared and checked above so there is
no need for it again.
Signed-off-by: NLuis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

net/mac80211/mlme.c

@@ -2076,10 +2076,6 @@ static int ieee80211_sta_config_auth(struct ieee80211_sub_if_data *sdata)
 		return 0;
 	} else {
 		if (ifmgd->assoc_scan_tries < IEEE80211_ASSOC_SCANS_MAX_TRIES) {
-			u8 ssid_len = 0;
-
-			if (!(ifmgd->flags & IEEE80211_STA_AUTO_SSID_SEL))
-				ssid_len = ifmgd->ssid_len;
 
 			ifmgd->assoc_scan_tries++;