V4L/DVB (5641): change VideoNorm to NTSC for Belkin USB Videobus II

Signed-off-by: David Warman <dwarman@davidwarman.net>
Signed-off-by: Thierry MERLE <thierry.merle@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>