qemu: domain: Validate support for LUKS encryption of QCOW2 images
qemu: domain: Validate support for LUKS encryption of QCOW2 images

Reject configurations when qemu would not support the image.

Signed-off-by: Peter Krempa <2cf5c04c61aa466e4a47bfedc747d17279c72ffc@redhat.com>

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