vt: keyboard: Don't process Unicode characters in K_OFF mode

We don't process Unicode characters if the virtual terminal is in raw
mode, so there's no reason why we shouldn't do the same for K_OFF
(especially since people would expect K_OFF to actually turn off all VT
key processing).

Fixes: 9fc3de9 ("vt: Add virtual console keyboard mode OFF")
Signed-off-by: Myrrh Periwinkle <myrrhperiwinkle@qtmlabs.xyz>
Cc: stable <stable@kernel.org>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20250702-vt-misc-unicode-fixes-v1-1-c27e143cc2eb@qtmlabs.xyz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: msizanoen1

drivers/tty/vt/keyboard.c

@@ -1487,7 +1487,7 @@ static void kbd_keycode(unsigned int keycode, int down, bool hw_raw)
 		rc = atomic_notifier_call_chain(&keyboard_notifier_list,
 						KBD_UNICODE, &param);
 		if (rc != NOTIFY_STOP)
-			if (down && !raw_mode)
+			if (down && !(raw_mode || kbd->kbdmode == VC_OFF))
 				k_unicode(vc, keysym, !down);
 		return;
 	}