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>

crypto/rsa/rsa_lib.c

@@ -243,8 +243,7 @@ void RSA_free(RSA *r)
         BN_BLINDING_free(r->blinding);
     if (r->mt_blinding != NULL)
         BN_BLINDING_free(r->mt_blinding);
-    if (r->bignum_data != NULL)
-        OPENSSL_free_locked(r->bignum_data);
+    OPENSSL_free_locked(r->bignum_data);
     OPENSSL_free(r);
 }