Update fan added / removed to use string

Fan names aren't always fan %d, sometimes there are numbers
too, or identifiers like CPU Fan 1. Change the argument to
a string.

Tested: Launched bmcweb and saw:

{
    "@odata.context": "/redfish/v1/$metadata#LogEntry.LogEntry",
    "@odata.id": "/redfish/v1/Systems/system/LogServices/EventLog/Entries/#1556037042",
    "@odata.type": "#LogEntry.v1_4_0.LogEntry",
    "Created": "2019-04-23T16:30:42+00:00",
    "EntryType": "Event",
    "Id": "1556037042",
    "Message": "Fan 1 removed.",
    "MessageArgs": [
	"Fan 1"
    ],
    "MessageId": "OpenBMC.0.1.FanRemoved",
    "Name": "System Event Log Entry",
    "Severity": "OK"
},
{
    "@odata.context": "/redfish/v1/$metadata#LogEntry.LogEntry",
    "@odata.id": "/redfish/v1/Systems/system/LogServices/EventLog/Entries/#1556037055",
    "@odata.type": "#LogEntry.v1_4_0.LogEntry",
    "Created": "2019-04-23T16:30:55+00:00",
    "EntryType": "Event",
    "Id": "1556037055",
    "Message": "Fan 1 inserted.",
    "MessageArgs": [
	"Fan 1"
    ],
    "MessageId": "OpenBMC.0.1.FanInserted",
    "Name": "System Event Log Entry",
    "Severity": "OK"
},

Change-Id: Ic0d07ea1c96ee6a61caa912ecd091c2783f1d963
Signed-off-by: James Feist <james.feist@linux.intel.com>
diff --git a/redfish-core/include/registries/openbmc_message_registry.hpp b/redfish-core/include/registries/openbmc_message_registry.hpp
index 662aa88..319f663 100644
--- a/redfish-core/include/registries/openbmc_message_registry.hpp
+++ b/redfish-core/include/registries/openbmc_message_registry.hpp
@@ -129,10 +129,10 @@
         "FanInserted",
         {
             .description = "Indicates that a system fan has been inserted.",
-            .message = "Fan %1 inserted.",
+            .message = "%1 inserted.",
             .severity = "OK",
             .numberOfArgs = 1,
-            .paramTypes = {"number"},
+            .paramTypes = {"string"},
             .resolution = "None.",
         }},
     MessageEntry{"FanRedundancyLost",
@@ -160,10 +160,10 @@
         "FanRemoved",
         {
             .description = "Indicates that a system fan has been removed.",
-            .message = "Fan %1 removed.",
-            .severity = "Warning",
+            .message = "%1 removed.",
+            .severity = "OK",
             .numberOfArgs = 1,
-            .paramTypes = {"number"},
+            .paramTypes = {"string"},
             .resolution = "None.",
         }},
     MessageEntry{