Medium: VirtualDomain: Add support for qemu-dm as emulator (bnc#885292)

When using Xen, qemu-dm is the emulator name. This patch ensures that
pid_status returns sensible information when this is the case.
Merge pull request #450 from krig/suse-vdomain

Medium: VirtualDomain: Add support for qemu-dm as emulator (bnc#885292)