qemu: Block blockjobs when transient disk option is enabled
qemu: Block blockjobs when transient disk option is enabled

For now we disallow blockjobs with transient disks to avoid dealing with
obsoleted overlays.

Signed-off-by: Masayoshi Mizuma <d5fddbc10d7d0c19347bebdeca1e9c9f92c33d10@jp.fujitsu.com>
Reviewed-by: Ján Tomko <4cab11cfb98d3c937327354a78eb07dbb6ee2bc6@redhat.com>
Tested-by: Ján Tomko <4cab11cfb98d3c937327354a78eb07dbb6ee2bc6@redhat.com>

libvirt/libvirt,jardasgit/libvirt,libvirt/libvirt,olafhering/libvirt,crobinso/libvirt,nertpinx/libvirt,libvirt/libvirt,zippy2/libvirt,nertpinx/libvirt,nertpinx/libvirt,jfehlig/libvirt,zippy2/libvirt,jfehlig/libvirt,olafhering/libvirt,jardasgit/libvirt,crobinso/libvirt,libvirt/libvirt,jfehlig/libvirt,zippy2/libvirt,crobinso/libvirt,crobinso/libvirt,jardasgit/libvirt,nertpinx/libvirt,zippy2/libvirt,olafhering/libvirt,olafhering/libvirt,jardasgit/libvirt,nertpinx/libvirt,jardasgit/libvirt,jfehlig/libvirt