[Bug driver/112759] [13/14 regression] mips -march=native detection broken with gcc 13+

[matoro_gcc_bugzilla at matoro dot tk]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112759

--- Comment #3 from matoro <matoro_gcc_bugzilla at matoro dot tk> ---
(In reply to Andrew Pinski from comment #2)
> Hmm, looks like it is this part of the change:
> +  if (cpu)
> +    ret = reconcat (ret, ret, "-m", argv[0], "=", cpu, NULL);
>  
> -  return concat ("-m", argv[0], "=", cpu, NULL);
> 
> 
> Maybe it should have been:
> ```
> if (cpu)
>   {
>     if (!ret)
>       ret = concat ("-m", argv[0], "=", cpu, NULL);
>     else
>       ret = reconcat (ret, ret, "-m", argv[0], "=", cpu, NULL);
>   }
> ```
> 
> Can you try that?

Indeed fixes it, thanks!