Squash using #if 0 a longstanding TODO to avoid warnings

Seen on Ubuntu 18.04 with
gcc version 7.5.0 (Ubuntu 7.5.0-3ubuntu1~18.04)
giving:

test_cipher.c: In function ‘test_cipher’:
test_cipher.c:299:19: error: suggest braces around empty body in an ‘if’ statement [-Werror=empty-body]
  /* XXXX check  */;
                   ^
cc1: all warnings being treated as errors

Signed-off-by: Andrew Bartlett <abartlet@samba.org>

lib/hcrypto/test_cipher.c

@@ -295,8 +295,11 @@ test_cipher(int i, const EVP_CIPHER *c, struct tests *t)
 	hex_encode(d, t->datasize, &s);
 	errx(1, "%s: %d decrypt not the same: %s", t->name, i, s);
     }
+
+#if 0 /* TODO */
     if (t->outiv)
 	/* XXXX check  */;
+#endif
 
     EVP_CIPHER_CTX_cleanup(&ectx);
     EVP_CIPHER_CTX_cleanup(&dctx);