Add history section for dd(1)
First version of UNIX to include dd found using TUHS
http://minnie.tuhs.org/cgi-bin/utree.pl?file=V5/usr/source/s1/dd.c
PR: 211777
Approved by: bcr (mentor)
MFC after: 5 days
Differential Revision: https://reviews.freebsd.org/D8104