media: v4l2-compat-ioctl32.c: drop pr_info for unknown buffer type

There is nothing wrong with using an unknown buffer type. So
stop spamming the kernel log whenever this happens. The kernel
will just return -EINVAL to signal this.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: <stable@vger.kernel.org>      # for v4.15 and up
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>