* configure.ac: Check for inet_ntop.
* m4/libcurl.m4: Provide a #define for the version of the curl
library.
* keyserver/gpgkeys_hkp.c (main, srv_replace): Call getaddrinfo() on
each target. Once we find one that resolves to an address (whether
IPv4 or IPv6), pass it into libcurl via CURLOPT_RESOLVE using the
SRV name as the "host". Force the HTTP Host header to be the same.
Backported from 6b1f71055ebab36989e2089cfde319d2ba40ada7
* keyserver/gpgkeys_hkp.c (main): Only default try-dns-srv to on if we
have SRV support in the first place.
Backported from 732f3d1d4786239db5f31f82cc04ec79326cc13c
5c557a51cd