ncurses 6.2 - patch 20211002

ncurses 6.2 - patch 20211002

+ use return-value from vsnprintf to reallocate as needed to allow for
  buffers larger than the screen size (report by "_RuRo_").
+ modify tset "-q" option to refrain from modifying terminal modes, to
  match the documentation.
+ add section on margins to terminfo.5, adapted from X/Open Curses.
+ make tput/tset warning messages consistently using alias names when
  those are used, rather than the underlying program's name.
+ improve tput usage message for aliases such as clear, by eliminating
  tput-specific portions.
+ add a check in toe to ensure that a "termcap file" is text rather
  than binary.
+ further build-fixes for OpenBSD 6.9, whose header files differ from
  the other BSDs.