[media] rtl2832: do not filter out slave TS null packets

Do not remove slave TS NULL padding PID (0x1fff) by default as
there is no real need. After that whole TS is passed to kernel sw
PID filter.

Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>