Fix exp/run in case kernel.sched_schedstats does not exist (ter)

exp/run

@@ -95,7 +95,9 @@ prepare_system() {
     msg "# Preparing system"
 
     sudo sysctl kernel.numa_balancing=0   >/dev/null
-    sudo sysctl kernel.sched_schedstats=1 >/dev/null 2>&1
+    if sysctl kernel.sched_schedstats >/dev/null 2>&1; then
+	sudo sysctl kernel.sched_schedstats=1 >/dev/null
+    fi
 }
 
 dump_system() {
@@ -260,7 +262,9 @@ move_results() {
 }
 
 cleanup_system() {
-    sudo sysctl kernel.sched_schedstats=0 >/dev/null 2>&1
+    if sysctl kernel.sched_schedstats >/dev/null 2>&1; then
+	sudo sysctl kernel.sched_schedstats=0 >/dev/null
+    fi
 }
 
 script=$0