devel/cdecl: update 18.2 → 18.3
Changelog:
https://github.com/paul-j-lucas/cdecl/releases/tag/cdecl-18.3
Also:
- replace PORTVERSION with DISTVERSION
- add LICENSE_FILE
- remove GNU_CONFIGURE_MANPREFIX
- move PLIST_FILES to pkg-plist
- pet portclippy
PR: 280878
Approved by: ler (maintainer)