V4L/DVB: drivers/media/dvb/siano: Remove double test

The same expression is tested twice and the result is the same each time.

The sematic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@expression@
expression E;
@@

(
* E
  || ... || E
|
* E
  && ... && E
)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>