PEL: Add UnknownSystemType error to message_registry

The following commit introduced this new error-
https://gerrit.openbmc-project.xyz/c/openbmc/openpower-vpd-
parser/+/49080

Signed-off-by: Alpana Kumari <alpankum@in.ibm.com>
Change-Id: I05a90e21b7cb8a57b52b092464cd3c9154c54960
diff --git a/extensions/openpower-pels/registry/message_registry.json b/extensions/openpower-pels/registry/message_registry.json
index 2304672..b71487b 100644
--- a/extensions/openpower-pels/registry/message_registry.json
+++ b/extensions/openpower-pels/registry/message_registry.json
@@ -3042,6 +3042,37 @@
         },
 
         {
+            "Name": "com.ibm.VPD.Error.UnknownSystemType",
+            "Subsystem": "cec_vpd",
+            "ComponentID": "0x4000",
+
+            "SRC": {
+                "ReasonCode": "0x4006",
+                "Words6To9":
+                {
+                }
+            },
+
+            "Callouts": [
+                {
+                   "CalloutList": [
+                        { "Priority": "high", "LocCode": "P0" }
+                    ]
+                }
+            ],
+
+            "Documentation": {
+                "Description": "Unknown System Type",
+                "Message": "System type not supported in DTB table.",
+                "Notes": [
+                    "System type comes from combination of HW and IM value of system VPD.",
+                    "If anything gets changed in that combination, then it can't determine",
+                    "the appropriate DTB for that system. Need to check HW and IM keywords."
+                ]
+            }
+        },
+
+        {
             "Name": "org.open_power.Host.Boot.Error.WatchdogTimeout",
             "Subsystem": "cec_sp_hostboot_iface",