x11/plasma6-plasma: Unpipewire kde6

[vvd]

Summary

Allow to build and work without pipewire.

But it does not prevent "silent grab" of libpipewire-0.3.so:multimedia/pipewire and libKPipeWire.soaudio/plasma6-kpipewire (USE_KDE=kpipewire).
To prevent "silent grab" it is necessary to patch CMakeList.txt for each port in list:

• sysutils/plasma6-kinfocenter
• x11-wm/plasma6-kwin
• x11/plasma6-plasma-desktop
• x11/plasma6-plasma-workspace
• x11/plasma6-plasma

[makc]

I'm not going to consider PIPEWIRE or any other option for KDE ports until it supported upstream. Moreover, in kde@ we often don't even make options for ports when they are supported upstream and the reason is plain simple: we do not have enough time and manpower to maintain all possible combination of options for a huge chunk software like KDE ports.

[vvd]

This is not just some build option - it is an opportunity to get rid of unnecessary bloatware in the system (like pulseaudio or avahi).

[makc]

Discussion with upstream: https://bugs.kde.org/show_bug.cgi?id=499828

[vvd]

In D49009#1118524, @makc wrote:

Discussion with upstream: https://bugs.kde.org/show_bug.cgi?id=499828

The link contains a discussion (+patch) of the possibility of build and work spectacle without pipewire. Unlike spectacle, the ports mentioned in this review can be build and run without pipewire, but for some reason this dependency was made mandatory in the ports.

[vvd]

Add patch for sysutils/plasma6-kinfocenter.