vt: ucs.c: fix misappropriate in_range() usage

The in_range() helper accepts a start and a length, not a start and
an end.

Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20250507141535.40655-2-nico@fluxnic.net


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>