MFC: Merge sendmail 8.14.6 errata issue
MFH r247014, r247050 and r247051.

Add a sample program that shows how a custom comparison function and
qsort(3) can work together to sort an array of integers.

PR:             docs/176197
Submitted by:   Fernando, fapesteguia at opensistemas.com
		Christoph Mallon, christoph.mallon at gmx.de
Approved by:    gjb (mentor), remko (mentor)
MFC r247334:

Correct a typo introduced in r153575, which gives inverted logic when
handling blocking semantics when seeding.

PR:		kern/143298
Submitted by:	James Juran <james juran baesystems com>
Reviewed by:	markm