Fix warnings.

engine/engine.c

@@ -685,7 +685,7 @@ static void parse_option_engine_builtin (const char *name, int arg, int *var, in
   assert (vasprintf (&h, help, ap) >= 0);
   va_end (ap);
 
-  parse_option_ex (name, arg, var, val, flags, f_parse_option_engine, h);
+  parse_option_ex (name, arg, var, val, flags, f_parse_option_engine, "%s", h);
 
   free (h);
 }

net/net-crypto-dh.c

@@ -147,7 +147,7 @@ void create_g_a (unsigned char g_a[256], unsigned char a[256]) {
     rpc_BN_ctx = BN_CTX_new ();
   }
   do {
-    assert (RAND_pseudo_bytes (a, 256) >= 0); /* if you write '>0', the assert will fail. It's very sad */
+    assert (RAND_bytes (a, 256) >= 0); /* if you write '>0', the assert will fail. It's very sad */
 
     BIGNUM *dh_power = BN_new ();
     assert (BN_bin2bn (a, 256, dh_power) == dh_power);