Implement TERMINAL_DIMENSIONS op for the terminal device, CE add terminfo command

kernel/device/device.c

@@ -86,6 +86,7 @@ struct device* device_create (const char* key, device_op_func_t* ops, size_t ops
 void terminal_device_init (void) {
   device_op_func_t ops[] = {
       [TERMINAL_PUTSTR] = &terminal_putstr,
+      [TERMINAL_DIMENSIONS] = &terminal_dimensions,
   };
   device_create ("TERMINAL", ops, lengthof (ops), &terminal_init, &terminal_fini, NULL);
 }