Fix DCPowerOff.NumberOfArgs Mandatory prop

The RedfishServiceValidator throws the following error:
"ERROR - Messages.DCPowerOff.NumberOfArgs: Mandatory prop
does not exist" for #MessageRegistry.v1_0_0.MessageRegistry.

From https://redfish.dmtf.org/schemas/MessageRegistry.v1_0_0.json
            "required": [
                "Description",
                "Message",
                "Severity",
                "NumberOfArgs",
                "Resolution"
            ],

Tested: Loaded this change on a Witherspoon, ran
        RedfishServiceValidator and no longer observe the
        error.
Change-Id: I9ccf3703bc6b06d2bd74f548e1bd4e2badd68c07
Signed-off-by: Gunnar Mills <gmills@us.ibm.com>
diff --git a/static/redfish/v1/Registries/OpenBMC/OpenBMC.0.1.0.json b/static/redfish/v1/Registries/OpenBMC/OpenBMC.0.1.0.json
index 3e13058..572061d 100644
--- a/static/redfish/v1/Registries/OpenBMC/OpenBMC.0.1.0.json
+++ b/static/redfish/v1/Registries/OpenBMC/OpenBMC.0.1.0.json
@@ -109,13 +109,15 @@
             "Description": "Indicates that the system DC power is off.",
             "Message": "Host system DC power is off",
             "Severity": "OK",
-            "Resolution": "None."
+            "Resolution": "None.",
+            "NumberOfArgs": 0
         },
         "DCPowerOn": {
             "Description": "Indicates that the system DC power is on.",
             "Message": "Host system DC power is on",
             "Severity": "OK",
-            "Resolution": "None."
+            "Resolution": "None.",
+            "NumberOfArgs": 0
         }
     }
-}
\ No newline at end of file
+}