qca: update to 2.2.1 for botan2 compatibility

[yan12125 (Chih-Hsuan Yen)]

According to some recent commits of qca (1), proper botan2 support is available since qca 2.2.0. As botan2 is needed for OpenSSL 1.1 (2), could you update qca?

Note that from qca commit messages, the latest version of qca is still compatible with botan 1.x, so there are two possible approaches:

1. Update qca to 2.2.1 and revbump qca when the botan port is updated to 2.10.0.
2. Update qca to 2.2.1 and botan to 2.10.0 at the same time. If you prefer this approach, I will push my WIP branch (3) to the main repo (macports/macports-ports) and you can push qca 2.2.1 to that branch.

I'm fine with either approach.

(1) ​https://github.com/KDE/qca/search?o=desc&q=botan&s=committer-date&type=Commits

(2) ticket:58513

(3) ​https://github.com/yan12125/macports-ports/tree/botan2

[yan12125 (Chih-Hsuan Yen)]

Done with ​https://github.com/macports/macports-ports/pull/4565.