Removed the callback_list_len argument from bf_process_byfl_file()

callback_list_len was being used as a crude sanity check that a client
program was compiled against the same version of the bfbin library
that's dynamically linked at run time.  I'm hopeful that simply
following the Libtool guidelines for versioning will prevent
compile-time vs. run-time library mismatches.

This version of Byfl was tested against revision 220498 of LLVM,
Clang, and DragonEgg.