pgsql: Remove replacement code for getaddrinfo.

Remove replacement code for getaddrinfo.

SUSv3, all targeted Unixes and modern Windows have getaddrinfo() and
related interfaces.  Drop the replacement implementation, and adjust
some headers slightly to make sure that the APIs are visible everywhere
using standard POSIX headers and names.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CA%2BhUKG%2BL_3brvh%3D8e0BW_VfX9h7MtwgN%3DnFHP5o7X2oZucY9dg%40mail.gmail.com

Branch
------
master

Details
-------
https://git.postgresql.org/pg/commitdiff/5579388d2dda60ded329a4623f9b4529e91a1b24

Modified Files
--------------
config/c-library.m4                   |  11 -
configure                             |  42 ----
configure.ac                          |  11 -
src/backend/libpq/auth.c              |   1 +
src/backend/libpq/hba.c               |   1 +
src/bin/initdb/initdb.c               |   3 +-
src/include/common/ip.h               |   4 +-
src/include/getaddrinfo.h             | 162 -------------
src/include/libpq/libpq-be.h          |   8 -
src/include/pg_config.h.in            |   6 -
src/include/port/win32/netdb.h        |   8 +
src/include/replication/walreceiver.h |   4 +-
src/interfaces/libpq/fe-connect.c     |   1 +
src/interfaces/libpq/libpq-int.h      |   3 +-
src/port/Makefile                     |   4 -
src/port/getaddrinfo.c                | 439 ----------------------------------
src/tools/msvc/Mkvcbuild.pm           |   2 +-
src/tools/msvc/Solution.pm            |   2 -
18 files changed, 22 insertions(+), 690 deletions(-)