Change AdditionalDataURI to be a child URI

Make the AdditionalDataURI a child relationship of the resource to better follow Hypermedia API best practices and match the AdditionalDataURI of the coming Post Code log entries.
Changed the AdditionalDataURI for bmc dump, system dump, and log entry

A hypermedia API gives us a search form in response and tells API what URL to use, which HTTP verb is appropriate, and what parameters to supply.

  URL change:-
  Old:
    "/redfish/v1/Systems/system/LogServices/EventLog/attachment/<str>"
  New:
    "/redfish/v1/Systems/system/LogServices/EventLog/Entries/<str>/attachment"

 #205

Tested: Validator passes.
- Verified the new AdditionalDataURI was correct for /redfish/v1/Systems/system/LogServices/EventLog/Entries:
$ curl -k https://w15.aus.stglabs.ibm.com/redfish/v1/Systems/system/LogServices/EventLog/Entries/1
{
  "@odata.id": "/redfish/v1/Systems/system/LogServices/EventLog/Entries/1",
  "@odata.type": "#LogEntry.v1_8_0.LogEntry",
  "AdditionalDataURI": "/redfish/v1/Systems/system/LogServices/EventLog/Entries/1/attachment",
  "Created": "2021-03-15T18:47:26+00:00",
  "EntryType": "Event",
  "Id": "1",
  "Message": "xyz.openbmc_project.Common.Error.InternalFailure",
  "Modified": "2021-04-30T17:26:38+00:00",
  "Name": "System Event Log Entry",
  "Resolved": true,
  "Severity": "Critical"
}

Change-Id: Ifb720ac2710ebd4a2df37a83c9deb8a6eefdffd5
Signed-off-by: Abhishek Patel <Abhishek.Patel@ibm.com>

redfish-core/lib/log_services.hpp

@@ -511,18 +511,16 @@ inline void
                 {
                     thisEntry["DiagnosticDataType"] = "Manager";
                     thisEntry["AdditionalDataURI"] =
-                        "/redfish/v1/Managers/bmc/LogServices/Dump/"
-                        "attachment/" +
-                        entryID;
+                        "/redfish/v1/Managers/bmc/LogServices/Dump/Entries/" +
+                        entryID + "/attachment";
                 }
                 else if (dumpType == "System")
                 {
                     thisEntry["DiagnosticDataType"] = "OEM";
                     thisEntry["OEMDiagnosticDataType"] = "System";
                     thisEntry["AdditionalDataURI"] =
-                        "/redfish/v1/Systems/system/LogServices/Dump/"
-                        "attachment/" +
-                        entryID;
+                        "/redfish/v1/Systems/system/LogServices/Dump/Entries/" +
+                        entryID + "/attachment";
                 }
             }
             asyncResp->res.jsonValue["Members@odata.count"] =
@@ -636,19 +634,17 @@ inline void
                 {
                     asyncResp->res.jsonValue["DiagnosticDataType"] = "Manager";
                     asyncResp->res.jsonValue["AdditionalDataURI"] =
-                        "/redfish/v1/Managers/bmc/LogServices/Dump/"
-                        "attachment/" +
-                        entryID;
+                        "/redfish/v1/Managers/bmc/LogServices/Dump/Entries/" +
+                        entryID + "/attachment";
                 }
                 else if (dumpType == "System")
                 {
                     asyncResp->res.jsonValue["DiagnosticDataType"] = "OEM";
                     asyncResp->res.jsonValue["OEMDiagnosticDataType"] =
                         "System";
                     asyncResp->res.jsonValue["AdditionalDataURI"] =
-                        "/redfish/v1/Systems/system/LogServices/Dump/"
-                        "attachment/" +
-                        entryID;
+                        "/redfish/v1/Systems/system/LogServices/Dump/Entries/" +
+                        entryID + "/attachment";
                 }
             }
             if (foundDumpEntry == false)
@@ -1508,8 +1504,8 @@ class DBusEventLogEntryCollection : public Node
                     {
                         thisEntry["AdditionalDataURI"] =
                             "/redfish/v1/Systems/system/LogServices/EventLog/"
-                            "attachment/" +
-                            std::to_string(*id);
+                            "Entries/" +
+                            std::to_string(*id) + "/attachment";
                     }
                 }
                 std::sort(entriesArray.begin(), entriesArray.end(),
@@ -1659,8 +1655,8 @@ class DBusEventLogEntry : public Node
                 {
                     asyncResp->res.jsonValue["AdditionalDataURI"] =
                         "/redfish/v1/Systems/system/LogServices/EventLog/"
-                        "attachment/" +
-                        std::to_string(*id);
+                        "Entries/" +
+                        std::to_string(*id) + "/attachment";
                 }
             },
             "xyz.openbmc_project.Logging",
@@ -1761,10 +1757,10 @@ class DBusEventLogEntryDownload : public Node
 {
   public:
     DBusEventLogEntryDownload(App& app) :
-        Node(
-            app,
-            "/redfish/v1/Systems/system/LogServices/EventLog/attachment/<str>/",
-            std::string())
+        Node(app,
+             "/redfish/v1/Systems/system/LogServices/EventLog/Entries/<str>/"
+             "attachment",
+             std::string())
     {
         entityPrivileges = {
             {boost::beast::http::verb::get, {{"Login"}}},