if usb device is the primaryGpu, the device unplug kwin_wayland exit
` } else if (device->action() == QStringLiteral("remove")) {
DrmGpu *gpu = findGpu(device->devNum());
if (gpu) {
if (primaryGpu() == gpu) {
qCCritical(KWIN_DRM) << "Primary gpu has been removed! Quitting...";
QCoreApplication::exit(1);
return;
} else {
gpu->setRemoved();
updateOutputs();
}
}`
This fixes the drm backend adding hotplugged gpus that belong to other
seats and makes the udev helper depend on less stuff from the layer
above backends.
The Session can be useful not only to the platform backend but also
input backends and for things such as vt switching, etc. Therefore it's
better to have the Application own the Session.
