MFC r335319, r335354, r335374

r335319:
audit(4): add tests for send, recv, sendto, and recvfrom

Submitted by: aniketp
Sponsored by: Google, Inc. (GSoC 2018)
Differential Revision: https://reviews.freebsd.org/D15869

r335354:
audit(4): add tests for ioctl(2)

Submitted by: aniketp
Sponsored by: Google, Inc. (GSoC 2018)
Differential Revision: https://reviews.freebsd.org/D15872

r335374:
audit(4): add tests for utimes(2) and friends, mprotect, and undelete

Includes utimes(2), futimes(2), lutimes(2), futimesat(2), mprotect(2), and
undelete(2). undelete, for now, is tested only in failure mode.

Submitted by: aniketp
Sponsored by: Google, Inc. (GSoC 2018)
Differential Revision: https://reviews.freebsd.org/D15893