Fix a bug in create_ssl_ctx_pair()

The max protocol version was only being set on the server side. It should
have been done on both the client and the server.
Reviewed-by: NRichard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6113)

test/ssltestlib.c

@@ -531,10 +531,10 @@ int create_ssl_ctx_pair(const SSL_METHOD *sm, const SSL_METHOD *cm,
         goto err;
     if (clientctx != NULL
         && ((min_proto_version > 0
-             && !TEST_true(SSL_CTX_set_min_proto_version(serverctx,
+             && !TEST_true(SSL_CTX_set_min_proto_version(clientctx,
                                                          min_proto_version)))
             || (max_proto_version > 0
-                && !TEST_true(SSL_CTX_set_max_proto_version(serverctx,
+                && !TEST_true(SSL_CTX_set_max_proto_version(clientctx,
                                                             max_proto_version)))))
         goto err;