mod_carboncopy: Apply small code simplification

src/mod_carboncopy.erl

@@ -171,14 +171,10 @@ send_copies(JID, To, Packet, Direction)->
 	_ -> {0, undefined}
     end,
 
+    %% unavailable resources are handled like bare JIDs
     IsBareTo = case {Direction, To} of
 	{received, #jid{lresource = <<>>}} -> true;
-	{received, #jid{lresource = LRes}} ->
-	    %% unavailable resources are handled like bare JIDs
-	    case lists:keyfind(LRes, 2, PrioRes) of
-		false -> true;
-		_ -> false
-	    end;
+	{received, #jid{lresource = LRes}} -> not lists:member(LRes, AvailRs);
 	_ -> false
     end,
     %% list of JIDs that should receive a carbon copy of this message (excluding the