Bug#973537: ausweisapp2: Backporting 1.20.2-1 to buster requires small patch

[A. Klitzing]

Hi there,

argh, sorry about that. We fixed some Qt 5.10 issues and the last
feature introduced a new incompatibility.
Your patch looks good! Thanks.

By the way.... 1.22.0 requires at least Qt 5.12.0.

Best regards
   André