Log Message:
textproc/libxml2: Fix undefined addrinfo on glibc

On Fedora 39 (only with IPv6 enabled):

  nanoftp.c: In function 'xmlNanoFTPConnect':
  nanoftp.c:798:25: error: storage size of 'hints' isn't known
    798 |         struct addrinfo hints, *tmp, *result;
        |                         ^~~~~

netdb.h and GNU's getaddrinfo(3) show that it's behind a feature macro:

  _POSIX_C_SOURCE >= 200112L

Tested on Fedora 39 and NetBSD 9.