media: dvb: Increase the limit on number of section filters

The number of section filters was limited to 64. However, real
limitation is the number of unique PID filter that can be opened
with the TSPPv2 hardware.

Change-Id: I5ec39dc641f560cf2e5d4c8828152d15aa42ae6a
Signed-off-by: Gilad Broner <gbroner@codeaurora.org>