close_range: add audit support

This fixes the closefrom test in sys/audit.

Includes cherry-picks of the following commits from openbsm:

https://github.com/openbsm/openbsm/commit/4dfc628aafe589d68848f7033f3d3488c4d979e0
https://github.com/openbsm/openbsm/commit/99ff6fe32aebc5a4b8d40d60062b8574697df557
https://github.com/openbsm/openbsm/commit/da48a0399e95448693d3fa2be48454ca564c1be8

Reviewed By: kevans
Differential Revision: https://reviews.freebsd.org/D28388

(cherry picked from commit fa32350347b4e351a144b5423f0fb2ca9d67f4ca)