It cannot upgrade the bluetooth-rfkill-event-hciattach as it doesn't exist in the repo. (I am not sure why.) This means you need to remove this package, and probably the broadcom-bluetooth as well) before you do a pkcon refresh. As the Bluetooth doesn't work on 3.4 anyway, it doesn't hurt if you remove these two packages. The 4.0 full install is available in my signature.