[media] dvb-frontend: remove a warning
[media] dvb-frontend: remove a warning

if CONFIG_MEDIA_CONTROLLER_DVB is not selected, it is now
producing this warning:

drivers/media/dvb-core/dvb_frontend.c: In function ‘dvb_frontend_thread’:
drivers/media/dvb-core/dvb_frontend.c:695:6: warning: unused variable ‘ret’ [-Wunused-variable]
  int ret;
      ^

Reported-by: Hans Verkuil <3a513708f73c27e7d36ebc496aa41dad6a3153ea@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <ad86ba2154032c9f55743a190faa2459a9d61d42@osg.samsung.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs