bio/bss_dgram.c: harmonize usage of OPENSSL_USE_IPV6 with the rest.
@@ -364,7 +364,7 @@ static long dgram_get_mtu_overhead(bio_dgram_data *data)
*/
ret = 28;
break;
-# ifdef AF_INET6
+# if OPENSSL_USE_IPV6
case AF_INET6:
{
# ifdef IN6_IS_ADDR_V4MAPPED
