Update development version from 10.66 (Nov. 14, 2017) to recent 12.14.

Changelog: https://exiftool.org/history.html

Submitted by takefu@airport.fm in PR 252047

Tested on Poudriere (amd64, i386). 'portlint -AC' is ok.

I would commit the patch with 'maintainer timeout', since maintainer Jin-Sih Lin <linpct@gmail.com> did not react for weeks now (2020-12-22).