Eliminating "tuple expression" overhead

[si14]

For now, alog_pt makes following:
?DBG({A, B, "test ~p"}, [foobar]) → dbg(io_lib:format("A: ~p B: ~p ~s", [A, B, "test ~p"]), [foobar])
There is another way to do this with less overhead:
?DBG({A, B, "test ~p"}, [foobar]) → dbg("A: ~p B: ~p test ~p", [A, B, foobar])