monitor: Use QERR_INVALID_PARAMETER instead of QERR_INVALID_CPU_INDEX

This changes the error message from "Invalid CPU index" to "Invalid
parameter index" in the human monitor.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

monitor.c

@@ -907,7 +907,7 @@ static void do_cpu_set(Monitor *mon, const QDict *qdict, QObject **ret_data)
 {
     int index = qdict_get_int(qdict, "index");
     if (mon_set_cpu(index) < 0)
-        qemu_error_new(QERR_INVALID_CPU_INDEX);
+        qemu_error_new(QERR_INVALID_PARAMETER, "index");
 }
 
 static void do_info_jit(Monitor *mon)