V4L/DVB (3352): Some fixes to compat_ioctl32

- Adds suppport or fix support for VIDIOC_ENUMSTD, VIDIOC_ENUMINPUT,
VIDIOC_G_TUNER and VIDIOC_S_TUNER.
- Fix the warnings at compile time and add checks for the pointer validity
using access_ok().
- v4l_print_ioctl() has also be added to identify possible missing ioctls.
- Has been tested on sparc64 and amd64. Other arches such as mips and hppa
are expected to work as sparc, but not tested yet.

Signed-off-by: Guy Martin <gmsoft@tuxicoman.be>
Signed-off-by: Mauro Carvalho Chehab <mchehab@brturbo.com.br>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>