[rennes] Add Renater network link

data/grid5000/sites/rennes/network_equipments/c6509-grid.json

@@ -8,7 +8,17 @@
 
     },
     {
+      "kind": "virtual",
+      "naming_pattern": "Te%LINECARD%/%PORT%",
+      "ports": [
+        {
 
+        },
+        {
+          "uid": "renater-rennes"
+        }
+      ],
+      "rate": 10000000000
     },
     {
       "kind": "node",