[media] lirc_dev: get irctl from irctls by inode again

Can't explain it (yet), but I've seen the 'get irctl via private_data'
setup fail for a number of people (ioctl called before its filled in?),
so lets go back to a variant of the old way, but one that still works
with unlocked_ioctl.

Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>