net/bmon: Update from 3.3 to 4.0

[joneum]

Summary

• net/bmon: Update from 3.3 to 4.0
• Changelog: https://github.com/tgraf/bmon/blob/master/NEWS

PR: 219392
Reported by: Eric Camachat
Approved by: [e-mail] (maintainer timeout, 2 weeks), xxxx (mentor)
#Differential Revision: https://reviews.freebsd.org/Dxxxxx

Test Plan

~/dev/ports/net/bmon % portlint -AC
WARN: Makefile: for new port, make $FreeBSD$ tag in comment section empty, to make SVN happy.
WARN: /usr/home/joneum/dev/ports/net/bmon/files/patch-src_in_sysctl.c: patch was not generated using `make makepatch''. It is recommended to use `make makepatch'' when you need to [re-]generate a patch to ensure proper patch format.
0 fatal errors and 2 warnings found.

poudriere testport:

10amd64
10i386
11amd64
11i386
12.0-CURRENT r318899 amd64
12.0-CURRENT r318400 i386