add missing unregister of no_prng

testprof/pkcs_1_pss_test.c

@@ -47,6 +47,8 @@ int pkcs_1_pss_test(void)
     mp_clear_multi(key->d,  key->e, key->N, key->dQ, key->dP, key->qP, key->p, key->q, NULL);
   } /* for */
 
+  unregister_prng(&no_prng_desc);
+
   return 0;
 }