Update comments

include/nuttx/input/ajoystick.h

@@ -199,6 +199,7 @@ struct ajoy_notify_s
 struct ajoy_sample_s
 {
   ajoy_buttonset_t as_buttons; /* State of all buttons */
+                               /* Possibly padded with 1 byte here */
   int16_t          as_x;       /* X/horizontal position */
   int16_t          as_y;       /* Y/vertical position */
 };

include/nuttx/input/mouse.h

@@ -74,6 +74,7 @@
 struct mouse_report_s
 {
   uint8_t  buttons;  /* See TOUCH_* definitions above */
+                     /* Possibly padded with 1 byte here */
   int16_t  x;        /* X coordinate of the mouse position */
   int16_t  y;        /* Y coordinate of the mouse position */
 #ifdef CONFIG_MOUSE_WHEEL