ejabberd_stun: Rename Logger filter

Don't overwrite the Logger filter added by the 'stun' application (which
appends metadata to STUN/TURN log messages).

Closes processone/stun#31.

src/ejabberd_stun.erl

@@ -212,8 +212,8 @@ init_logger() ->
     ok.
 -else.
 init_logger() ->
-    case logger:add_primary_filter(stun, {fun ?MODULE:stun_filter/2,
-					  ?STUN_MAX_LOG_LEVEL}) of
+    case logger:add_primary_filter(ejabberd_stun, {fun ?MODULE:stun_filter/2,
+						   ?STUN_MAX_LOG_LEVEL}) of
 	ok ->
 	    ok;
 	{error, {already_exist, _}} ->