Making PipeWire required for xdp-kde

[Jan Grulich]

Hi,

I recently pushed a background portal implementation, which also needs some 
KWayland stuff, while previously it was needed just for screen sharing purpose 
and compiled only when PipeWire and some other libraries are found. Now I need 
the Wayland part available all the time and I don't want to use idefs all over 
the place to disable most of the Wayland code in case of PipeWire is not 
found. Because of that, I'm thinking of making PipeWire and remaining libs 
(GBM, Epoxy) as required. What do you think? PipeWire is already available 
basically everywhere and this way users won't miss screen sharing support in 
case packagers forget to add PipeWire as dependency.

Optional dependencies are mentioned here:
https://cgit.kde.org/xdg-desktop-portal-kde.git/tree/CMakeLists.txt#n23

Here you can see that Wayland integration part is built only when screen 
sharing is enabled:
https://cgit.kde.org/xdg-desktop-portal-kde.git/tree/src/CMakeLists.txt#n37

Thank you for your opinions.

Regards,
Jan