tests: vmstate static checker: incompat machine types

This commit modifies the dump2 data to flag incompatibilities in the
machine types being compared.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Acked-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>

tests/vmstate-static-checker-data/dump2.json

@@ -1,6 +1,6 @@
 {
   "vmschkmachine": {
-    "Name": "pc-i440fx-2.1"
+    "Name": "pc-i440fx-2.2"
   },
   "fw_cfg": {
     "Name": "fw_cfg",