Unnecessary output emitted for lua

This is really only cosmetic but as the snippet below shows, the generated output unnecessarily has ';' and also the return statement is unnecessarily encapsulated in do ... end

Its not 100% but often

```lua
Date.fromTime = function(t)
local d = _hx_e();
_G.setmetatable(d, _hx_o({__fields__={__index=true},__index=Date.prototype}));
d.t = t / 1000;
d.d = _G.os.date("*t", Std.int(d.t));
do return d end;
end
```