[media] cx23885: handle errors from videobuf_dvb_get_frontend()

The error handling in the original code wasn't complete so static
checkers complained about a potential NULL deference.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
1 file changed