ncurses 6.2 - patch 20210710

ncurses 6.2 - patch 20210710

+ improve history section for tset manpage based on the 1BSD tarball,
  which preceded BSD's SCCS checkins by more than three years.
+ improve CF_XOPEN_CURSES macro used in test/configure (report by Urs
  Jansen).
+ further improvement of libtool configuration, adding a dependency of
  the install.tic rule, etc., on the library in the build-tree.
+ update config.sub