Fix build with NETGRAPH_MPPC_COMPRESSION but without NETGRAPH_MPPC_ENCRYPTION.
Fix build with NETGRAPH_MPPC_COMPRESSION but without NETGRAPH_MPPC_ENCRYPTION.

Approved by:	glebius (mentor)

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