tools: print the key as -1 for obfuscated keys

Missing from 8c1aa1de where we hid the human-readable parts but the keycode
itself is still enough information to recover the typed bits.
Print it as -1 as that keycode doesn't exist for real keys so it stands out
nicely.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>

tools/event-debug.c

@@ -294,6 +294,7 @@ print_key_event(struct libinput *li, struct libinput_event *ev)
 	if (!options->show_keycodes &&
 	    (key >= KEY_ESC && key < KEY_ZENKAKUHANKAKU)) {
 		keyname = "***";
+		key = -1;
 	} else {
 		keyname = libevdev_event_code_get_name(EV_KEY, key);
 		keyname = keyname ? keyname : "???";