free cleanup almost the finale

Add OPENSSL_clear_free which merges cleanse and free.
(Names was picked to be similar to BN_clear_free, etc.)
Removed OPENSSL_freeFunc macro.
Fixed the small simple ones that are left:
        CRYPTO_free CRYPTO_free_locked OPENSSL_free_locked

Reviewed-by: Richard Levitte <levitte@openssl.org>
diff --git a/ssl/ssl_cert.c b/ssl/ssl_cert.c
index 0ae9646..a15c5f9 100644
--- a/ssl/ssl_cert.c
+++ b/ssl/ssl_cert.c
@@ -465,11 +465,8 @@
     custom_exts_free(&c->cli_ext);
     custom_exts_free(&c->srv_ext);
 #endif
-    if (c->pms) {
-        OPENSSL_cleanse(c->pms, c->pmslen);
-        OPENSSL_free(c->pms);
-        c->pms = NULL;
-    }
+    OPENSSL_clear_free(c->pms, c->pmslen);
+    c->pms = NULL;
     OPENSSL_free(c);
 }