phosh/{phosh,phoc,squeekboard}: remove, upstreamed

I've upstreamed the packages to Alpine Linux, @Cogitri is now the maintainer. https://gitlab.alpinelinux.org/alpine/aports/merge_requests/2714

Although this doesn't really fix #407 (closed), at least we don't cross-compile squeekboard anymore. Should still be fixed for other Rust packages however.