Add message entry for IPMI watchdog event

Log the IPMI watchdog event into redfish.

Tested:
Set a hard reset watchdog:
ipmitool raw 0x06 0x24 0x5 0x1 0x0 0x0 0x64 0x00
Start the timer:
ipmitool mc watchdog reset

Check the below log message in
https://$bmcip/redfish/v1/Systems/system/LogServices/EventLog/Entries

"Message": "Host Watchdog Event: Hard Reset – System reset due to Watchdog timeout",
            "MessageArgs": [
                "Hard Reset – System reset due to Watchdog timeout"
            ],
            "MessageId": "OpenBMC.0.1.IPMIWatchdog",

Signed-off-by: Yong Li <yong.b.li@linux.intel.com>
Change-Id: I652faf3b92489b2dd3216eb0cbaaf375e643c749
diff --git a/redfish-core/include/registries/openbmc_message_registry.hpp b/redfish-core/include/registries/openbmc_message_registry.hpp
index f85f025..55b5299 100644
--- a/redfish-core/include/registries/openbmc_message_registry.hpp
+++ b/redfish-core/include/registries/openbmc_message_registry.hpp
@@ -281,6 +281,21 @@
                 },
             .resolution = "None.",
         }},
+
+    MessageEntry{
+        "IPMIWatchdog",
+        {
+            .description = "Indicates that there is a host watchdog event.",
+            .message = "Host Watchdog Event: %1",
+            .severity = "OK",
+            .numberOfArgs = 1,
+            .paramTypes =
+                {
+                    "string",
+                },
+            .resolution = "None.",
+        }},
+
     MessageEntry{
         "LegacyPCIPERR",
         {