postmarketos-fde-unlocker: make unl0kr the default

I'll need some more time to test this. Have been fighting severe network issues this evening so this is just a blind patch so far.

Fixes: #1411 (closed)

TODO:

• https://gitlab.com/cherrypicker/unl0kr/-/issues/34
• https://gitlab.com/cherrypicker/unl0kr/-/issues/36 (at least good enough)
• new unl0kr version in pmaports with fixes for the above issues
• !3777 (closed)