Jian-Hong Pan authored Mar 28, 2019 and Benjamin Berg committed Mar 28, 2019

The Acer Veriton Z4660G/Z4860G/Z6860G series AIO desktops have a
brightness button in the bottom.  The KEY_BRIGHTNESS_CYCLE event will be
sent from ACPI video module in kernel when the button is pressed.

This commit adds the binding for the KEY_BRIGHTNESS_CYCLE event sent
from the button as a media-key.

#117