V4L/DVB (10921): msp3400: remove obsolete V4L1 code

There are no drivers left that call msp3400 with V4L1 commands. Remove it
from this driver.

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>