-[viaccess] Fixed CW checksum bytes for viaccess 2
-Added support for a higher number of demux devices in CA PMT
(Modern enigma2 boxes with FCB tuners can have many demux devices,
so a new CA PMT descriptor that allows up to 128 demuxes (descriptor tag 0x86) is now supported.
Also, the get_demux_options() function is completely re-written,
so it doesn't care for the order of descriptors inside the CA PMT message)