piix: Move pc-0.13 virtio-9p-pci compat to PC_COMPAT_0_13

The compat property was added by commit
9dbcca5a, and the pc-0.12 and older
machine-types were not changed because virtio-9p-pci was introduced on QEMU
0.13 (commit 9f107513). The only problem is
that this breaks the PC_COMPAT_* nesting pattern we currently use.

So, move the property to PC_COMPAT_0_13. This make pc-0.12 and older inherit
it, but that shouldn't be an issue as QEMU 0.12 didn't have virtio-9p-pci.

Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

hw/i386/pc_piix.c

@@ -838,6 +838,10 @@ static QEMUMachine pc_machine_v0_14 = {
             .driver   = "AC97",\
             .property = "use_broken_id",\
             .value    = stringify(1),\
+        },{\
+            .driver   = "virtio-9p-pci",\
+            .property = "vectors",\
+            .value    = stringify(0),\
         },
 
 #define PC_I440FX_0_13_MACHINE_OPTIONS \
@@ -850,10 +854,6 @@ static QEMUMachine pc_machine_v0_13 = {
     .compat_props = (GlobalProperty[]) {
         PC_COMPAT_0_13
         {
-            .driver   = "virtio-9p-pci",
-            .property = "vectors",
-            .value    = stringify(0),
-        },{
             .driver   = "VGA",
             .property = "rombar",
             .value    = stringify(0),