sysutils/procenv: Update to 0.55
- Take MAINTAINER'ship
- reorder Makefile (portclippy)
- deleted files/patch-configure.ac and files/patch-src_platform_freebsd_platform-freebsd.h
because changes were included upstream
ChangeLog: https://github.com/jamesodhunt/procenv/blob/0.55/NEWS
Reviewed by: daniel.engberg.lists@pyret.net
Approved by: dbaio, garga (mentors)
Differential Revision: https://reviews.freebsd.org/D29689