tests: vmstate static checker: remove a section

Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Reviewed-by: NJuan Quintela <quintela@redhat.com>
Signed-off-by: NJuan Quintela <quintela@redhat.com>

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

@@ -2,7 +2,7 @@
   "vmschkmachine": {
     "Name": "pc-i440fx-2.2"
   },
-  "fw_cfg": {
+  "fw_cfg2": {
     "Name": "fw_cfg",
     "version_id": 2,
     "minimum_version_id": 1,