V4L/DVB (13025): s2250-board: Fix memory leaks

In some error cases, allocated buffers need to be freed before returning.

Signed-off-by: Pete Eberlein <pete@sensoray.com>
Signed-off-by: Douglas Schilling Landgraf <dougsland@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>