Compile ToolTalk on FreeBSD

Compile ToolTalk on FreeBSD

Fix const correctness problems with OPT_CONST_CORRECT:

tt_xdr_utils.C: In constructor '_Tt_xdr_size_stream::_Tt_xdr_size_stream()':
tt_xdr_utils.C:150: error: invalid conversion from 'bool_t (*)(__rpc_xdr*, long int*)' to 'bool_t (*)(__rpc_xdr*, const long int*)'
tt_xdr_utils.C:151: error: invalid conversion from 'bool_t (*)(__rpc_xdr*, char*, unsigned int)' to 'bool_t (*)(__rpc_xdr*, const char*, u_int)'
tt_xdr_utils.C:159: error: invalid conversion from 'bool_t (*)(__rpc_xdr*, char*, unsigned int)' to 'bool_t (*)(__rpc_xdr*, const char*, u_int)'

tt_entry_pt.C: In function '_Tt_string _tt_entrypt_to_string(_Tt_entry_pt)':
tt_entry_pt.C:455: error: conversion from 'long int' to '_Tt_string' is ambiguous
../../lib/util/tt_string.h:104: note: candidates are: _Tt_string::_Tt_string(int)
../../lib/util/tt_string.h:102: note:                 _Tt_string::_Tt_string(const char*)