master
Update ncurses and associated libraries (form, panel, menu) to 6.4-20230826 (from 5.7-20081102).
Avoid snprintf() of NULL when _nc_get_source() returns NULL. The filename buffer is not actually used in this case but it is safer to set it to the empty string than to leave it uninitialized. OK tb@
create pkg-config files for curses-related libraries makes sense to kettenis & feedback about compiler/linker flags ok tb, millert
Update to ncurses 5.7, with local changes reapplied.
Fix some program names that were not expanded correctly when ncurses was updated and were instead replaced by ?. ok millert