Don't include libarchive fuzz tests by default

Don't include libarchive fuzz tests by default

These tests are basic fuzz tests that permute input to trigger crashes
rather than regression or unit tests. Additionally, some of them take a
rather long time to run and should probably be run on a dedicated fuzzing
job instead. Moreover, these simple tests use rand() instead of a real
fuzzing tool that generates interesting inputs (e.g. LLVM libFuzzer) so are
unlikely to find anything interesting when run in CI.

This allows removing one BROKEN_TESTS case due to timeouts and speeds up
running tests on emulated platforms such as QEMU.

Reviewed By:	lwhsu, mm
Differential Revision: https://reviews.freebsd.org/D27153

(cherry picked from commit 3454fa118c41a588e2dad20614325297c989c60b)