[m-rev.] for post-commit review: simplify code writing out LLDS C code

[Julien Fischer]

On Sat, 1 Oct 2022, Zoltan Somogyi wrote:

> Simplify the code writing out LLDS C code.
> 
> compiler/llds_out_util.m:
>     Add decl_set_insert_new, which combines decl_set_is_member and
>     decl_set_insert in their typical usage pattern.
> 
> compiler/layout_out.m:
> compiler/llds_out_code_addr.m:
> compiler/llds_out_data.m:
> compiler/llds_out_file.m:
> compiler/llds_out_global.m:
> compiler/llds_out_instr.m:
> compiler/rtti_out.m:
>     Use decl_set_insert_new where applicable.
>
>     Replace sequences of calls to io.write_{string,int}s with calls to
>     io.format.

That's fine.

Julien.