v4l: Remove reference to bkl ioctl in compat ioctl handling

There are no more users of struct file_operations:ioctl. These
can be safely removed.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Mauro Carvalho Chehab <mchehab@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Hans Verkuil <hverkuil@xs4all.nl>