Including <sys/errno.h> instead of <errno.h> raises a compiler warning
when building against musl libc. Always include <errno.h> instead of
<sys/errno.h> to prevent that compilation warning from being triggered
and to achieve consistency in this regard across the entire source tree.
(cherry picked from commit b5cd146033)
4708. [cleanup] Legacy Windows builds (i.e. for XP and earlier)
are no longer supported. [RT #45186]
4707. [func] The lightweight resolver daemon and library (lwresd
and liblwres) have been removed. [RT #45186]
4706. [func] Code implementing name server query processing has
been moved from bin/named to a new library "libns".
Functions remaining in bin/named are now prefixed
with "named_" rather than "ns_". This will make it
easier to write unit tests for name server code, or
link name server functionality into new tools.
[RT #45186]