At daemon startup we query logind for host PM support status. Without
a service dependency host startup can trigger libvirtd errors like:

error : virNodeSuspendSupportsTarget:336 : internal error: Cannot probe for
supported suspend types
warning : virQEMUCapsInit:949 : Failed to get host power management
capabilities

https://bugzilla.redhat.com/show_bug.cgi?id=1588288Reviewed-by: NAndrea Bolognani <abologna@redhat.com>
Signed-off-by: NCole Robinson <crobinso@redhat.com>