V4L/DVB (3743): Fix some more potential oopses

Spotted a couple more places where it fails to check if
dvb_register_adapter() fails.

Signed-off-by: Andrew de Quincey <adq_dvb@lidskialf.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2 files changed