z7 uart0 buffered read

bsp_z7/newlib/write.c

@@ -22,7 +22,7 @@ int _write(int fd, const char *ptr, int len) {
   }
   // we only support a single debug UART, so
   // stdout and stderr are the same and go to the xiling stdout UART
-  // TODO switch to a hw_interface_write() instead?
+  // We output directely to avoid loops and allow debugging (not via a write)
   if (fd < 3) {
     int todo;