vt: update gen_ucs_width_table.py to make tables more space efficient

Split table ranges into BMP (16-bit) and non-BMP (above 16-bit).
This reduces the corresponding text size by 20-25%.

Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20250417184849.475581-13-nico@fluxnic.net


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