trivial: debian: recusively cleanup on purge
trivial: debian: recusively cleanup on purge

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