tests: Sync qemucaps2xml with qemucapabilities

Commits d7434ae8 and 9c4afbda added replies files for
QEMU 3.0.0 on s390x and QEMU 3.1.0 on x86_64 respectively, but
only enabled the corresponding test in qemucapabilities and not
in qemucaps2xml.
Signed-off-by: NAndrea Bolognani <abologna@redhat.com>

tests/qemucaps2xmloutdata/caps_3.0.0.s390x.xml

+<capabilities>
+
+  <host>
+    <cpu>
+      <arch>s390x</arch>
+    </cpu>
+    <power_management/>
+    <iommu support='no'/>
+  </host>
+
+  <guest>
+    <os_type>hvm</os_type>
+    <arch name='s390x'>
+      <wordsize>64</wordsize>
+      <emulator>/usr/bin/qemu-system-s390x</emulator>
+      <domain type='qemu'/>
+      <domain type='kvm'/>
+    </arch>
+    <features>
+      <cpuselection/>
+      <deviceboot/>
+      <disksnapshot default='on' toggle='no'/>
+    </features>
+  </guest>
+
+</capabilities>

tests/qemucaps2xmloutdata/caps_3.1.0.x86_64.xml

+<capabilities>
+
+  <host>
+    <cpu>
+      <arch>x86_64</arch>
+    </cpu>
+    <power_management/>
+    <iommu support='no'/>
+  </host>
+
+  <guest>
+    <os_type>hvm</os_type>
+    <arch name='x86_64'>
+      <wordsize>64</wordsize>
+      <emulator>/usr/bin/qemu-system-x86_64</emulator>
+      <domain type='qemu'/>
+      <domain type='kvm'/>
+    </arch>
+    <features>
+      <cpuselection/>
+      <deviceboot/>
+      <disksnapshot default='on' toggle='no'/>
+      <acpi default='on' toggle='yes'/>
+      <apic default='on' toggle='no'/>
+    </features>
+  </guest>
+
+</capabilities>

tests/qemucaps2xmltest.c

@@ -200,6 +200,7 @@ mymain(void)
     DO_TEST("x86_64", "caps_2.11.0");
     DO_TEST("x86_64", "caps_2.12.0");
     DO_TEST("x86_64", "caps_3.0.0");
+    DO_TEST("x86_64", "caps_3.1.0");
     DO_TEST("aarch64", "caps_2.6.0");
     DO_TEST("aarch64", "caps_2.10.0");
     DO_TEST("aarch64", "caps_2.12.0");
@@ -215,6 +216,7 @@ mymain(void)
     DO_TEST("s390x", "caps_2.10.0");
     DO_TEST("s390x", "caps_2.11.0");
     DO_TEST("s390x", "caps_2.12.0");
+    DO_TEST("s390x", "caps_3.0.0");
     DO_TEST("riscv32", "caps_3.0.0");
     DO_TEST("riscv64", "caps_3.0.0");