Enable/disable crypto-mdebug just like other features

Also always abort() on leak failure.

Reviewed-by: Stephen Henson <steve@openssl.org>
diff --git a/test/ssltest.c b/test/ssltest.c
index c3d655e..d6b6618 100644
--- a/test/ssltest.c
+++ b/test/ssltest.c
@@ -1821,7 +1821,7 @@
     ERR_free_strings();
     ERR_remove_thread_state(NULL);
     EVP_cleanup();
-#ifdef CRYPTO_MDEBUG
+#ifndef OPENSSL_NO_CRYPTO_MDEBUG
     CRYPTO_mem_leaks(bio_err);
 #endif
     BIO_free(bio_err);