qemu: dump: Report better error when dumping VM with passthrough devices
qemu: dump: Report better error when dumping VM with passthrough devices

For the regular dump operation we migrate the VM to a file. This won't
work when the VM has passthrough devices assigned. Rather than reporting
a cryptic error from qemu run our check whether it can be migrated.

This does not influence the memory-only dump that is allowed with
passthrough devices.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=874418

olafhering/libvirt,taget/libvirt,agx/libvirt,olafhering/libvirt,jardasgit/libvirt,crobinso/libvirt,zippy2/libvirt,jardasgit/libvirt,eskultety/libvirt,crobinso/libvirt,andreabolognani/libvirt,crobinso/libvirt,nertpinx/libvirt,elmarco/libvirt,taget/libvirt,elmarco/libvirt,rlaager/libvirt,taget/libvirt,eskultety/libvirt,fabianfreyer/libvirt,elmarco/libvirt,nertpinx/libvirt,rlaager/libvirt,fabianfreyer/libvirt,shugaoye/libvirt,VenkatDatta/libvirt,zippy2/libvirt,jfehlig/libvirt,andreabolognani/libvirt,VenkatDatta/libvirt,zippy2/libvirt,datto/libvirt,nertpinx/libvirt,rlaager/libvirt,eskultety/libvirt,datto/libvirt,andreabolognani/libvirt,shugaoye/libvirt,jardasgit/libvirt,agx/libvirt,jardasgit/libvirt,elmarco/libvirt,eskultety/libvirt,libvirt/libvirt,nertpinx/libvirt,agx/libvirt,taget/libvirt,nertpinx/libvirt,jfehlig/libvirt,jfehlig/libvirt,libvirt/libvirt,VenkatDatta/libvirt,shugaoye/libvirt,datto/libvirt,datto/libvirt,jardasgit/libvirt,fabianfreyer/libvirt,crobinso/libvirt,VenkatDatta/libvirt,andreabolognani/libvirt,rlaager/libvirt,rlaager/libvirt,fabianfreyer/libvirt,libvirt/libvirt,jfehlig/libvirt,fabianfreyer/libvirt,zippy2/libvirt,datto/libvirt,shugaoye/libvirt,taget/libvirt,libvirt/libvirt,VenkatDatta/libvirt,olafhering/libvirt,olafhering/libvirt,agx/libvirt,andreabolognani/libvirt,agx/libvirt,elmarco/libvirt,eskultety/libvirt,shugaoye/libvirt