mac80211: clean up key freeing a bit

When a key is allocated but not really added, there's no
need to go through the entire teardown process. Also, if
adding a key fails, ieee80211_key_link() can take care of
freeing it instead of the (only) caller.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/net/mac80211/key.h b/net/mac80211/key.h
index 2a682d8..8ef56cd 100644
--- a/net/mac80211/key.h
+++ b/net/mac80211/key.h
@@ -129,14 +129,13 @@
 					  size_t seq_len, const u8 *seq);
 /*
  * Insert a key into data structures (sdata, sta if necessary)
- * to make it used, free old key.
+ * to make it used, free old key. On failure, also free the new key.
  */
-int __must_check ieee80211_key_link(struct ieee80211_key *key,
-				    struct ieee80211_sub_if_data *sdata,
-				    struct sta_info *sta);
+int ieee80211_key_link(struct ieee80211_key *key,
+		       struct ieee80211_sub_if_data *sdata,
+		       struct sta_info *sta);
 void __ieee80211_key_free(struct ieee80211_key *key, bool delay_tailroom);
-void ieee80211_key_free(struct ieee80211_local *local,
-			struct ieee80211_key *key);
+void ieee80211_key_free_unused(struct ieee80211_key *key);
 void ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata, int idx,
 			       bool uni, bool multi);
 void ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata,