maint: move man-related syntax checks in cfg.mk

This is more natural, now that the top-level Makefile has access to
all the variables and rules once defined only in 'man/Makefile.am'

* man/local.mk (all_programs, sc_option_desc_uppercase,
sc_man_file_correlation check-x-vs-1, check-programs-vs-x): Move
from here ...
* cfg.mk: ... to here.  Adjust some comments in the process.

man/local.mk

@@ -181,43 +181,3 @@ $(MAN): $(top_srcdir)/src/system.h
 	  && rm -rf $$t							\
 	  && chmod -w $@-t						\
 	  && mv $@-t $@
-
-# Option descriptions should not start with a capital letter
-.PHONY: sc_option_desc_uppercase
-sc_option_desc_uppercase: $(dist_man1_MANS) $(NO_INSTALL_PROGS_DEFAULT:%=%.1)
-	@grep '^\\fB\\-' -A1 *.1 | LC_ALL=C grep '\.1.[A-Z][a-z]' && \
-	    { echo 1>&2 '$@: found initial capitals in --help';   \
-	      exit 1; } || :;
-
-.PHONY: sc_man_file_correlation
-sc_man_file_correlation: check-x-vs-1 check-programs-vs-x
-
-# Ensure that for each .x file in this directory, there is a
-# corresponding .1 file in the definition of $(dist_man1_MANS) above.
-# But since that expansion usually lacks programs like arch and hostname,
-# add them here manually.
-.PHONY: check-x-vs-1
-check-x-vs-1:
-	@PATH=./src$(PATH_SEPARATOR)$$PATH; export PATH;		\
-	t=$@-t;								\
-	(cd $(srcdir)/man && ls -1 *.x)					\
-	  | sed 's/\.x$$//' | $(ASSORT) > $$t;				\
-	(echo $(dist_man1_MANS) $(NO_INSTALL_PROGS_DEFAULT)		\
-	  | tr -s ' ' '\n' | sed 's/\.1$$//')				\
-	  | $(ASSORT) -u | diff - $$t || { rm $$t; exit 1; };		\
-	rm $$t
-
-all_programs =								\
-      (cd ./src && MAKEFLAGS= $(MAKE) -s all_programs.list)		\
-       | grep -v '\['
-
-.PHONY: check-programs-vs-x
-check-programs-vs-x:
-	@status=0;					\
-	for p in dummy `$(all_programs)`; do		\
-	  test $$p = dummy && continue;			\
-	  test $$p = ginstall && p=install || : ;	\
-	  test -f $(srcdir)/man/$$p.x			\
-	    || { echo missing $$p.x 1>&2; status=1; };	\
-	done;						\
-	exit $$status