Fixes "w_scan -f c" complaining with

  This dvb driver is *buggy*: the symbol rate limits are undefined - please
  report to linuxtv.org)
Signed-off-by: NDaniel Scheller <d.scheller@gmx.net>
Acked-by: NAbylay Ospan <aospan@netup.ru>
Cc: stable@vger.kernel.org
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>