io: fix FD socket handling in DNS lookup

The qio_dns_resolver_lookup_sync() method is required to be a no-op
for socket kinds that don't require name resolution. Thus the KIND_FD
handling should not return an error.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>

io/dns-resolver.c

@@ -158,16 +158,13 @@ int qio_dns_resolver_lookup_sync(QIODNSResolver *resolver,
 
     case SOCKET_ADDRESS_KIND_UNIX:
     case SOCKET_ADDRESS_KIND_VSOCK:
+    case SOCKET_ADDRESS_KIND_FD:
         return qio_dns_resolver_lookup_sync_nop(resolver,
                                                 addr,
                                                 naddrs,
                                                 addrs,
                                                 errp);
 
-    case SOCKET_ADDRESS_KIND_FD:
-        error_setg(errp, "Unsupported socket address type 'fd'");
-        return -1;
-
     default:
         abort();
     }