bug#57028: 29.0.50; Build error with configure when brew installed 12.1 libgccjit on macos

[Eli Zaretskii]

> From: Mark Barton <mbarton98@gmail.com>
> Date: Sun, 7 Aug 2022 00:15:09 -0700
> Cc: 57028@debbugs.gnu.org
> 
>  On Aug 6, 2022, at 11:29 PM, Eli Zaretskii <eliz@gnu.org> wrote:
> 
>  I hope some macOS expert could chime in and clarify the issues enough
>  for us to make the decisions.
> 
> 57015 has a more precise solution than mine in 57028 since it uses readlink 
> to follow the symbolic link to
> always get the path to the actual library. 

But we then established that 'readlink' cannot be relied upon to exist
on any random system.  So AFAIU, that solution cannot be used.