Suppress an "uknown option" warning when using no-dtls1 on Windows

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2567)

diff --git a/util/mk1mf.pl b/util/mk1mf.pl
index 7a3ae11f7865fe720764ac1b9276094db2c77f9d..490a034e4037e6d8eb35706914b46a5eca3acfb1 100755 (executable)
--- a/util/mk1mf.pl
+++ b/util/mk1mf.pl
@@ -1207,6 +1207,7 @@ sub read_options
                "no-ssl3-method" => 0,
                "no-tlsext" => \$no_tlsext,
                "no-tls1" => \$no_tls1,
+               "no-dtls1" => 0,
                "no-srp" => \$no_srp,
                "no-cms" => \$no_cms,
                "no-jpake" => \$no_jpake,