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It has not been needed for many years and gets in the way of
portable dumping, address sanitization, etc.  See:
https://lists.gnu.org/r/emacs-devel/2016-12/msg00147.html
* configure.ac (LDFLAGS_NOCOMBRELOC, emacs_cv_znocombreloc):
Remove.  All uses removed.
* etc/PROBLEMS: Remove discussion of combreloc problems.