V4L/DVB (12107): smscoreapi: fix compile warning

gcc 4.3.1 generates this warning:

v4l/smscoreapi.c: In function 'smscore_gpio_configure':
v4l/smscoreapi.c:1481: warning: 'GroupNum' may be used uninitialized in this function
v4l/smscoreapi.c:1480: warning: 'TranslatedPinNum' may be used uninitialized in this function

While in practice this will not happen, it is something that the compiler
can't determine. Initializing these two local variables to 0 suppresses
this warning.

Cc: Udi Atar <udi.linuxtv@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>