[nancy][grat] enable turbo boost

data/grid5000/sites/nancy/clusters/grat/nodes/grat-1.json

@@ -352,9 +352,9 @@
     "cstate_driver": "acpi_idle",
     "cstate_governor": "menu",
     "ht_enabled": true,
-    "pstate_driver": "none",
-    "pstate_governor": "none",
-    "turboboost_enabled": false
+    "pstate_driver": "acpi-cpufreq",
+    "pstate_governor": "performance",
+    "turboboost_enabled": true
   },
   "performance": {
     "core_flops": 33600000000,