#9 softcrc fails on 64-bit platforms

[Martti Kuutti]

dvbsnoop's '-softcrc' option fails under 64-bit platform (at least linux) due the use of u_long in src/misc/crc32.[ch]
To fix this, uint32_t could be used instead u_long. Patch 'crc32_64bitfix.patch' uploaded for fix.