trivial: Don't remove all flags when the device is removed
trivial: Don't remove all flags when the device is removed

We only really want to say 'the device is no longer updatable' and other flags
on the device (for instance, if it was locked) might still be useful.

superm1/fwupd,fwupd/fwupd,fwupd/fwupd,superm1/fwupd,vathpela/fwupd,hughsie/fwupd,hughsie/fwupd,fwupd/fwupd,hughsie/fwupd,vathpela/fwupd,fwupd/fwupd,vathpela/fwupd,vathpela/fwupd,hughsie/fwupd,superm1/fwupd