This is a bit hack, but returning error when driver is not tuned yet
causes DVBv5 zap stop polling DVBv5 statistics. Thus return 0 even
callback is called during invalid device state.
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>