[nancy] remove pdu information for clusters which have been relocated to the DCML

input/grid5000/sites/nancy/clusters/graffiti/graffiti_pdu.yaml

----
-nodes:
-  graffiti-1:
-    pdu:
-      - uid: graffiti-pdu1
-        port: 1
-      - uid: graffiti-pdu2
-        port: 1
-  graffiti-2:
-    pdu:
-      - uid: graffiti-pdu1
-        port: 6
-      - uid: graffiti-pdu2
-        port: 6
-  graffiti-3:
-    pdu:
-      - uid: graffiti-pdu1
-        port: 7
-      - uid: graffiti-pdu2
-        port: 7
-  graffiti-4:
-    pdu:
-      - uid: graffiti-pdu1
-        port: 14
-      - uid: graffiti-pdu2
-        port: 14
-  graffiti-5:
-    pdu:
-      - uid: graffiti-pdu1
-        port: 15
-      - uid: graffiti-pdu2
-        port: 15
-  graffiti-6:
-    pdu:
-      - uid: graffiti-pdu1
-        port: 21
-      - uid: graffiti-pdu2
-        port: 21
-  graffiti-7:
-    pdu:
-      - uid: graffiti-pdu1
-        port: 23
-      - uid: graffiti-pdu2
-        port: 23
-  graffiti-8:
-    pdu:
-      - uid: graffiti-pdu3
-        port: 3
-      - uid: graffiti-pdu4
-        port: 3
-  graffiti-9:
-    pdu:
-      - uid: graffiti-pdu3
-        port: 5
-      - uid: graffiti-pdu4
-        port: 5
-  graffiti-10:
-    pdu:
-      - uid: graffiti-pdu3
-        port: 7
-      - uid: graffiti-pdu4
-        port: 7
-  graffiti-11:
-    pdu:
-      - uid: graffiti-pdu3
-        port: 13
-      - uid: graffiti-pdu4
-        port: 13
-  graffiti-12:
-    pdu:
-      - uid: graffiti-pdu3
-        port: 17
-      - uid: graffiti-pdu4
-        port: 17
-  graffiti-13:
-    pdu:
-      - uid: graffiti-pdu3
-        port: 21
-      - uid: graffiti-pdu4
-        port: 21