mac80211: remove underscores from some key functions

Some key function don't exist without underscores, so
remove the underscores from those.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index c2d4bf2..e5c1441 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -252,7 +252,7 @@
 		goto out_unlock;
 	}
 
-	__ieee80211_key_free(key, true);
+	ieee80211_key_free(key, true);
 
 	ret = 0;
  out_unlock: