Add FreeBSD 8.1 to known list as it's being referenced by a couple of manpages already.
Add FreeBSD 8.1 to known list as it's being referenced by a couple of
manpages already.

MFC after:	3 days

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase