xcb: Adding and removing devices while the application is running may spam the application output with unregistered device messages

There are messages like this one which can be outputted >10 times in row:

qt.qpa.input.events: scroll event from unregistered device <#>

Probably any GUI application should be enough, but this might only reproduce with specific devices.

If this is just something that can happen in X normally, maybe Qt could be made to only report this once per device.