sysutils/mcelog: Update to v151

[dbaio]

Summary

sysutils/mcelog: Update to v151

- Compress some fields in mempage.
- Add coverity fixes
- mcelog version: Add ability for OS to define version

PR:	219573
Submitted by:	[e-mail] (maintainer)
Approved by:	garga (mentor)
Differential Revision:	https://reviews.freebsd.org/D10950

Test Plan

$ portlint -C
WARN: [...]/sysutils/mcelog/pkg-message: possible use of absolute pathname "/path/to/log".
0 fatal errors and 1 warning found.

poudriere testport:

10.3-RELEASE-p19 amd64
10.3-RELEASE-p19 i386
11.0-RELEASE-p10 amd64
11.0-RELEASE-p10 i386
12.0-CURRENT r318689 amd64
12.0-CURRENT r318690 i386