[media] pwc: Remove dev_hint module parameter

The code for this is rather crufty, and being able to tie a device
to a specific minor is not really something we want to support in
a modern udev based world.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>