MFC: Delete description of non-existent options: "-4" and "-6".
MFC: Delete description of non-existent options: "-4" and "-6".

MFC forgotten by:	motoyuki

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