Merge from 5.8.0 to 6.0.0 not correct

[Maik Qualmann]

Gilles, the merge from 5.8.0 to 6.0.0 is not complete. I had already wondered 
that 6.0.0 reacts worse on threads again. Do we have a chance to check what 
else is missing?

master:
https://cgit.kde.org/digikam.git/tree/libs/threads/actionthreadbase.cpp#n69
https://cgit.kde.org/digikam.git/tree/libs/threads/actionthreadbase.cpp#n88


6.0.0:
https://cgit.kde.org/digikam.git/tree/libs/threads/actionthreadbase.cpp?
h=development/6.0.0#n69
https://cgit.kde.org/digikam.git/tree/libs/threads/actionthreadbase.cpp?
h=development/6.0.0#n87

Maik