Remove 'optimization' to skip resolve_symlinks() when the found

Remove 'optimization' to skip resolve_symlinks() when the found
executable file isn't itself a symlink.  We still need to run the
algorithm so that any directory symlinks in the path to the
executable are replaced by a true path.  Noticed this on seeing
pg_config give me a completely wrong answer for --pkglibdir when
I called it through a symlink to the installation bindir.