Fix victim name shown in notification

From #52 :

  On Ubuntu 16.04, running as user (not as service) the
  notify-osd notification reported the correct PID but the
  wrong process name "gnome-system-monitor" when in fact
  killing whatsapp. The terminal output shows the correct PID
  and name.

Reason is that the wrong variable was used.

kill.c

@@ -214,7 +214,7 @@ static void userspace_kill(DIR* procdir, int sig, int ignore_oom_score_adj,
 
  char notif_args[200];
  snprintf(notif_args, sizeof(notif_args),
- "-i dialog-warning 'earlyoom' 'Killing process %d %s'", victim_pid, name);
+ "-i dialog-warning 'earlyoom' 'Killing process %d %s'", victim_pid, victim_name);
  maybe_notify(notif_command, notif_args);
  }