Introduce JERRY_ZSTR_ARG macro to avoid jerryx_print_string, jerryx_print_byte, jerry_port_print_byte, strlen (#4982)

Replace usage of jerryx_print_byte, jerryx_print_string with jerryx_print_buffer.

As we now have JERRY_ZSTR_ARG, so we can take advantage of it

With this, the jerry_port_print_byte port api won't need any more
this reduced the port api surface

JerryScript-DCO-1.0-Signed-off-by: Yonggang Luo luoyonggang@gmail.com

targets/os/nuttx/jerry-main.c

@@ -206,7 +206,7 @@ jerry_main (int argc, char *argv[])
 
   if (files_counter == 0)
   {
-    jerryx_repl ("jerry> ");
+    jerryx_repl (JERRY_ZSTR_ARG ("jerry> "));
   }
   else
   {