AOSA-2016-0018: update libarchive to 1:3.2.1-1

Please update your libarchive package to version 1:3.2.1-1.

Three recent Git master commit from libarchive fixed the following three security vulnerabilities:

CVE-2016-8687, CVE-2016-8688, CVE-2016-8689 (all reserved but not issued).

Relevant documentation:

• aosc-os-abbs issue #462, containing patch information.
• libarchive upstream issue #747.
• libarchive upstream issue #761.
• libarchive upstream issue #767.