Usage of KF5/KF6 in targets and CMake config files outside of Frameworks

[Heiko Becker]

Hi,

while looking at a MR for libkcddb (part of Gear) I wondered if the 
transition
from Qt5/KF5 to Qt6/KF6 could be used to get rid of the KF5/6 prefix in 
target
names and CMake config files for libraries that aren't acutally part of 
Frameworks.

It always seemed a bit illogical and possibly confusing to me to have e.g. 
KF5Cddb as CMake config file and KF5::Cddb as target name, because it's  
masquerading to be part of something (Frameworks), which isn't actually 
true.
Especially since we market Frameworks as a common group of libraries, with 
common rules and policies, which may only be followed in part (or maybe not 
at all) by other projects.

Changing that obviously involves some (temporary) compatibility concerns, 
but that doesn't play any role with the move to Qt6/KF6. So I suggest to 
use the chance and get rid of said prefix with the upcoming porting.

One example where this was done already some time ago is libkgapi: 
https://invent.kde.org/pim/libkgapi/-/commit/8d15e66f1ed87a52377111735e24888b7f924a49

Regards,
Heiko