Add information about the EVFILT_NETDEV filter
Add information about the EVFILT_NETDEV filter

PR:		docs/56872 (based on)
Submitted by:	Suleiman Souhlal <refugee@vt.edu>
Reviewed by:	hmp, jmg

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