games/anki: Update to 2.1.11, undeprecate and set to BROKEN

Undeprecate and save the port from the big Qt4 wipeout by switching from Qt4
to Qt5.

Also set games/anki temporarily as BROKEN because www/py-qt5-webengine is
still in a defunct state. This will change when www/qt5-webengine gets
updated to a more recent version soon (hopefully to the end of Q1).

At last but not least: Add options to switch between multimedia/mpv (new
default by upstream) and multimedia/mplayer (previous default) or choose both
of them.

Changelog:

Notable changes since 2.0.52:

• Anki 2.1.x uses the same scheduling, syncing and file format as Anki 2.0.x, so one can upgrade and downgrade at will.
• Switched from Python 2.7 to Python 3.6+ and from Qt 4 to Qt 5
• Add-ons will need to be updated to work with 2.1.
• Built in MathJax support
• A "restore backup" option in the profiles screen
• SVG rendering support for LaTeX
• Improved add-on configuration, management and updating
• Night mode for reviewing
• Improved pasting, with less unnecessary formatting included, and better handling of media links.

https://apps.ankiweb.net/docs/changes.html

PR: 233192
Approved by: miwi (mentor)
Differential Revision: https://reviews.freebsd.org/D19564