nl80211: fix memory leak when parsing NL80211_ATTR_HE_BSS_COLOR

If there is an error when parsing the NL80211_ATTR_HE_BSS_COLOR
attribute, we return immediately without freeing param.acl.  Fit it by
using goto out instead of returning immediately.

Fixes: 5c5e52d1bb ("nl80211: add handling for BSS color")
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20200626124931.7ad2a3eb894f.I60905fb70bd20389a3b170db515a07275e31845e@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/wireless/nl80211.c

@@ -5025,7 +5025,7 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
 					info->attrs[NL80211_ATTR_HE_BSS_COLOR],
 					&params.he_bss_color);
 		if (err)
-			return err;
+			goto out;
 	}
 
 	nl80211_calculate_ap_params(&params);