XF86keysym: Add XF86XK_MonBrightnessCycle

Add XF86XK_MonBrightnessCycle keysym, to be used as mapping for evdev's
KEY_BRIGHTNESS_CYCLE keycode which is generated from ACPI video module's
ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS on some Acer AIO desktop buttons.
The button changes the screen's brightness on Windows.

Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=108861Signed-off-by: Jian-Hong Pan <jian-hong@endlessm.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

include/X11/XF86keysym.h

@@ -23,11 +23,12 @@
 #define XF86XK_ModeLock		0x1008FF01	/* Mode Switch Lock */
 
 /* Backlight controls. */
-#define XF86XK_MonBrightnessUp   0x1008FF02  /* Monitor/panel brightness */
-#define XF86XK_MonBrightnessDown 0x1008FF03  /* Monitor/panel brightness */
-#define XF86XK_KbdLightOnOff     0x1008FF04  /* Keyboards may be lit     */
-#define XF86XK_KbdBrightnessUp   0x1008FF05  /* Keyboards may be lit     */
-#define XF86XK_KbdBrightnessDown 0x1008FF06  /* Keyboards may be lit     */
+#define XF86XK_MonBrightnessUp    0x1008FF02  /* Monitor/panel brightness */
+#define XF86XK_MonBrightnessDown  0x1008FF03  /* Monitor/panel brightness */
+#define XF86XK_KbdLightOnOff      0x1008FF04  /* Keyboards may be lit     */
+#define XF86XK_KbdBrightnessUp    0x1008FF05  /* Keyboards may be lit     */
+#define XF86XK_KbdBrightnessDown  0x1008FF06  /* Keyboards may be lit     */
+#define XF86XK_MonBrightnessCycle 0x1008FF07  /* Monitor/panel brightness */
 
 /*
  * Keys found on some "Internet" keyboards.