Revert "qemu: forbid migration with an IOMMU device"
Revert "qemu: forbid migration with an IOMMU device"

This reverts commit b7118623ad5a8e6ea75d693881c08873eefa3e28.

Migration was implemented by QEMU commit:
commit 8cdcf3c1e58d04b6811956d7608efeb66c42d719
Author: Peter Xu <peterx@redhat.com>
Date:   Fri Jan 6 12:06:13 2017 +0800

    intel_iommu: allow migration

https://bugzilla.redhat.com/show_bug.cgi?id=1433994

crobinso/libvirt,fabianfreyer/libvirt,nertpinx/libvirt,jfehlig/libvirt,olafhering/libvirt,andreabolognani/libvirt,libvirt/libvirt,eskultety/libvirt,fabianfreyer/libvirt,jfehlig/libvirt,VenkatDatta/libvirt,VenkatDatta/libvirt,jardasgit/libvirt,andreabolognani/libvirt,crobinso/libvirt,jfehlig/libvirt,datto/libvirt,fabianfreyer/libvirt,nertpinx/libvirt,datto/libvirt,zippy2/libvirt,eskultety/libvirt,jardasgit/libvirt,datto/libvirt,jardasgit/libvirt,libvirt/libvirt,zippy2/libvirt,olafhering/libvirt,eskultety/libvirt,nertpinx/libvirt,nertpinx/libvirt,eskultety/libvirt,fabianfreyer/libvirt,zippy2/libvirt,nertpinx/libvirt,VenkatDatta/libvirt,olafhering/libvirt,libvirt/libvirt,VenkatDatta/libvirt,datto/libvirt,fabianfreyer/libvirt,eskultety/libvirt,jfehlig/libvirt,zippy2/libvirt,datto/libvirt,libvirt/libvirt,andreabolognani/libvirt,jardasgit/libvirt,crobinso/libvirt,jardasgit/libvirt,VenkatDatta/libvirt,andreabolognani/libvirt,crobinso/libvirt,olafhering/libvirt,andreabolognani/libvirt