[nancy, rennes] new input files: fix model entries

dev/input/grid5000/sites/nancy/networks/sgraphene1.yaml

 ---
 sgraphene1:
-  model: 3com 451000000000
+  model: 3com 4510G
   kind: switch
   site: nancy
   snmp_community: public

dev/input/grid5000/sites/nancy/networks/sgraphene2.yaml

 ---
 sgraphene2:
-  model: 3com 451000000000
+  model: 3com 4510G
   kind: switch
   site: nancy
   snmp_community: public

dev/input/grid5000/sites/nancy/networks/sgraphene3.yaml

 ---
 sgraphene3:
-  model: 3com 451000000000
+  model: 3com 4510G
   kind: switch
   site: nancy
   snmp_community: public

dev/input/grid5000/sites/nancy/networks/sgraphene4.yaml

 ---
 sgraphene4:
-  model: 3com 451000000000
+  model: 3com 4510G
   kind: switch
   site: nancy
   snmp_community: public

dev/input/grid5000/sites/rennes/networks/c6509.yaml

@@ -13,7 +13,7 @@ c6509:
       snmp_pattern: TenGigabitEthernet%LINECARD%/%PORT%
       rate: 10000000000
       backplane_bps: 40000000000
-      model: WS-X6704-1000000000E
+      model: WS-X6704-10GE
       ports:
         2:
           uid: gw-rennes