Send GOST SignatureAlgorithms when TLS 1.2 in use

Reviewed-by: NBernd Edlinger <bernd.edlinger@hotmail.de>
Reviewed-by: NMatt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6168)

ssl/t1_lib.c

@@ -661,7 +661,12 @@ static const uint16_t tls12_sigalgs[] = {
 
     TLSEXT_SIGALG_dsa_sha256,
     TLSEXT_SIGALG_dsa_sha384,
-    TLSEXT_SIGALG_dsa_sha512
+    TLSEXT_SIGALG_dsa_sha512,
+#endif
+#ifndef OPENSSL_NO_GOST
+    TLSEXT_SIGALG_gostr34102012_256_gostr34112012_256,
+    TLSEXT_SIGALG_gostr34102012_512_gostr34112012_512,
+    TLSEXT_SIGALG_gostr34102001_gostr3411,
 #endif
 };