V4L/DVB: drivers/media/dvb/frontends/stv090x.c: fix use-uninitlalised

Mad guess.

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Manu Abraham <manu@linuxtv.org>
Acked-by: Manu Abraham <manu@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>