[COMMITTED] Remove TDF_THREADING flag in favor of param.

[Martin Liška]

On 11/9/21 15:36, Aldy Hernandez wrote:
> I don't see any ordering in these items, so I've placed it next to
> another of the backward threader knobs.
> 
> How does this look?

That's fine, thanks.

Note that similar --param 'ranger-debug' is also documented ;P

Cheers,
Martin