update path to Iot device SDK for C

Author: timlt

.openpublishing.redirection.iot-hub.json

@@ -1107,6 +1107,11 @@
       "source_path_from_root": "/articles/iot-hub/iot-hub-visual-studio-cloud-device-messaging.md",
       "redirect_url": "/azure/iot-hub/iot-hub-vscode-iot-toolkit-cloud-device-messaging",
       "redirect_document_id": false
+    },
+    {
+      "source_path_from_root": "/articles/iot-hub/azure/iot-hub/iot-c-sdk-ref/*",
+      "redirect_url": "https://github.com/Azure/azure-iot-sdk-c",
+      "redirect_document_id": false
     }
   ]
 }

articles/iot-hub/TOC.yml

@@ -574,7 +574,7 @@
       href: /python/api/azure-mgmt-iothub
     - name: C device SDK
       displayName: maps, buffers, batch, transport protocols, HTTP, AMQP, serialization, ANSI C (C99)
-      href: /azure/iot-hub/iot-c-sdk-ref/
+      href: https://github.com/Azure/azure-iot-sdk-c/
     - name: REST (Device)
       displayName: Abandon Device Bound Notification, Complete Device Bound Notification, Create File Upload Sas Uri, Get Device And Module In Scope, Get Devices And Modules In Scope, Receive Device Bound Notification, Send Device Event, Update File Upload Status
       href: /rest/api/iothub/device