mac80211: add back lost debugfs files

Somehow these files were never present or lost, but the code
is there and they seem somewhat useful, so add them back.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/net/mac80211/debugfs.c b/net/mac80211/debugfs.c
index f62cd0e..47bea0b 100644
--- a/net/mac80211/debugfs.c
+++ b/net/mac80211/debugfs.c
@@ -356,6 +356,7 @@ void debugfs_hw_add(struct ieee80211_local *local)
 
 	DEBUGFS_ADD(total_ps_buffered);
 	DEBUGFS_ADD(wep_iv);
+	DEBUGFS_ADD(rate_ctrl_alg);
 	DEBUGFS_ADD(queues);
 	DEBUGFS_ADD(misc);
 #ifdef CONFIG_PM