archivers/libarchive: Update to 3.5.2

Use GitHub as primary MASTER_SITE and libarchive.org as fallback
Enable Zstandard compression support by default
Use xz tarball instead of gz (smaller size)
Remove entries for DESC that are already defined in ports framework
Disable static library
Do some rearrangement of Makefile for readability

Changelog: https://github.com/libarchive/libarchive/releases/tag/v3.5.2

Approved by: arrowd (mentor), glewis (maintainer)
Differential Revision: https://reviews.freebsd.org/D32988