[PATCH v2] io: Use gnulib fts implementation (BZ 22944, BZ 20331)

[Collin Funk]

Wilco Dijkstra <Wilco.Dijkstra@arm.com> writes:

> Hi Adhemerval,
>
> +  size_t val = rotr_sz ((size_t) data, 3);
>
> Does it really make sense to add a new header reinventing the wheel rather than:
>
> size_t val = stdc_rotate_right ((size_t) data, 3);

That is a C2y function right? I don't think we can use it. Looking at
the releases with the relevant commit:

    $ git tag --contains 972f653cad2aedcfa901614566506c1c2e668766
    basepoints/gcc-16
    releases/gcc-15.1.0
    releases/gcc-15.2.0

Collin