community/notcurses: upgrade to 2.1.7

We now depend on readline. ncneofetch now has all the ascii logos from neofetch, and thus finally displays an image for Aline. If there's a good png/jpeg/gif/webm logo available on the filesystem somewhere, though, I'd much prefer using that!

--update--

updated to 2.1.7. This splits libnotcurses into libnotcurses-core and libnotcurses. Only the latter depends on the heavyweight multimedia dependency chain. I haven't split the two into distinct Alpine packages yet, but might in the future. Also, notcurses-view is now ncplayer.

is something wrong with the aarch64 builders?