rem: dev: Remove the log message about incomplete IPv6 API

The log message would not be ever reached, because the IPv6 API is
always considered to be complete.  Just remove the dead code.

Closes #5068

Merge branch '5068-remove-dead-code-from-ns_interface' into 'main'

See merge request isc-projects/bind9!9798

lib/ns/interfacemgr.c

@@ -845,12 +845,6 @@ purge_old_interfaces(ns_interfacemgr_t *mgr) {
 	}
 }
 
-static bool
-listenon_is_ip6_any(ns_listenelt_t *elt) {
-	REQUIRE(elt && elt->acl);
-	return dns_acl_isany(elt->acl);
-}
-
 static isc_result_t
 setup_locals(isc_interface_t *interface, dns_acl_t *localhost,
 	     dns_acl_t *localnets) {
@@ -1089,7 +1083,6 @@ do_scan(ns_interfacemgr_t *mgr, bool verbose, bool config) {
 	isc_netaddr_t zero_address, zero_address6;
 	ns_listenelt_t *le = NULL;
 	ns_interface_t *ifp = NULL;
-	bool log_explicit = false;
 	bool dolistenon;
 	char sabuf[ISC_SOCKADDR_FORMATSIZE];
 	bool tried_listening;
@@ -1226,19 +1219,6 @@ do_scan(ns_interfacemgr_t *mgr, bool verbose, bool config) {
 				}
 			}
 
-			if (log_explicit && family == AF_INET6 &&
-			    listenon_is_ip6_any(le))
-			{
-				isc_log_write(NS_LOGCATEGORY_NETWORK,
-					      NS_LOGMODULE_INTERFACEMGR,
-					      verbose ? ISC_LOG_INFO
-						      : ISC_LOG_DEBUG(1),
-					      "IPv6 socket API is "
-					      "incomplete; explicitly "
-					      "binding to each IPv6 "
-					      "address separately");
-				log_explicit = false;
-			}
 			isc_sockaddr_format(&listen_sockaddr, sabuf,
 					    sizeof(sabuf));
 			isc_log_write(NS_LOGCATEGORY_NETWORK,