The new function goes into print-openflow.c as vendor name decoding is
the same in all versions of OpenFlow (although in 1.0 it is "vendor"
and in subsequent versions it is "experimenter"). The mapping is from:
https://rs.opennetworking.org/wiki/display/PUBLIC/ONF+Registry
openflow.h in tcpdump doesn't belong to the openflow distribution and
shouldn't be attributed to stanford.edu (probably a copy-and-paste
case). Replace with 2-clause BSD.
