libvirt_vcpu_plug_unplug: adapt to s390x

S390x doesn't have ACPI (s3/s4), nor does it have cpu hot
unplug. Set values and filter accordingly for s390x.

Signed-off-by: Sebastian Mitterle <smitterl@redhat.com>

Author: smitterl

libvirt/tests/cfg/libvirt_vcpu_plug_unplug.cfg

@@ -14,6 +14,10 @@
     restart_libvirtd = "no"
     setvcpu_readonly = "no"
     topology_correction = "yes"
+    s390-virtio:
+        no suspend_to_mem, suspend_to_disk
+        vcpu_unplug = no
+        pin_before_unplug = no
     variants:
         - positive_test:
             status_error = "no"
@@ -60,7 +64,6 @@
                                     pin_vcpu = "0"
                                     pin_cpu_list = "x,y"
                                 - pin_unplug:
-                                    no s390-virtio
                                     vcpu_plug = "no"
                                     pin_before_unplug = "yes"
                                     pin_vcpu = "2"