/*
 * call-seq:
 *   easy.resolve_mode = symbol                             => symbol
 *
 * Configures what type of IP address this Curl::Easy instance
 * resolves DNS names to. Valid options are:
 *
 * [:auto]  resolves DNS names to all IP versions your system allows
 * [:ipv4]  resolves DNS names to IPv4 only
 * [:ipv6]  resolves DNS names to IPv6 only
 */
static VALUE ruby_curl_easy_resolve_mode_set(VALUE self, VALUE resolve_mode) {