mac80211: initialize return flags in HE 6 GHz operation parsing

Dan points out that if ieee80211_chandef_he_6ghz_oper() succeeds,
we don't initialize 'ret'. Initialize it to 0 in this case, since
everything went fine and nothing has to be disabled.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: 57fa5e85 ("mac80211: determine chandef from HE 6 GHz operation")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Link: https://lore.kernel.org/r/20200603111500.bd2a5ff37b83.I2c3f338ce343b581db493eb9a0d988d1b626c8fb@changeidSigned-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/mlme.c

@@ -167,6 +167,8 @@ ieee80211_determine_chantype(struct ieee80211_sub_if_data *sdata,
 			ret = IEEE80211_STA_DISABLE_HT |
 			      IEEE80211_STA_DISABLE_VHT |
 			      IEEE80211_STA_DISABLE_HE;
+		else
+			ret = 0;
 		vht_chandef = *chandef;
 		goto out;
 	}