amd64: Cleanup

ir/be/amd64/amd64_emitter.c

@@ -986,12 +986,9 @@ static void amd64_gen_block(ir_node *block)
  */
 static void amd64_gen_labels(ir_node *block, void *env)
 {
-	ir_node *pred;
-	int n = get_Block_n_cfgpreds(block);
-	(void) env;
-
-	for (n--; n >= 0; n--) {
-		pred = get_Block_cfgpred(block, n);
+	(void)env;
+	for (int n = get_Block_n_cfgpreds(block)-1; n >= 0; n--) {
+		ir_node *const pred = get_Block_cfgpred(block, n);
 		set_irn_link(pred, block);
 	}
 }