[rennes][roazhon2] update disk by path for roazhon2

data/grid5000/sites/rennes/clusters/roazhon2/nodes/roazhon2-1.json

@@ -89,7 +89,7 @@
   "storage_devices": [
     {
       "by_id": "",
-      "by_path": "/dev/disk/by-path/dummy",
+      "by_path": "/dev/disk/by-path/pci-0000:18:00.0-scsi-0:2:0:0",
       "id": "disk0",
       "interface": "SAS",
       "model": "unknown",

input/grid5000/sites/rennes/clusters/roazhon2/roazhon2.yaml

@@ -65,4 +65,4 @@ nodes:
         interface: SAS
         storage: SSD
         model: unknown
-        by_path: "/dev/disk/by-path/dummy"
+        by_path: "/dev/disk/by-path/pci-0000:18:00.0-scsi-0:2:0:0"