MFC r269867:
Update our stub resolver to final version of libbind
(libbind-6.0).

Obtained from:  ISC
MFC r269873:
Fix broken pointer overflow check ns_name_unpack()

Many compilers may optimize away the overflow check `msg + l < msg',
where `msg' is a pointer and `l' is an integer, because pointer
overflow is undefined behavior in C.

Use a safe precondition test `l >= eom - msg' instead.

Reference:
https://android-review.googlesource.com/#/c/50570/

Requested by:	pfg
Obtained from:	NetBSD (CVS rev. 1.10)
MFC r270215: Add missing break.
MFC r270643:
Fix typo: s/mac_rev/mac_ver/

Submitted by:	Stefan Sperling <stsp at openbsd dot org>