Linux input enumerator

[chyyran]

Helpful links:

• https://archive.is/ASdPI

• https://github.com/dolphin-emu/dolphin/blob/4733bbd8f38c0583aed0fd2faa2c9d577456bcfe/Source/Core/InputCommon/ControllerInterface/evdev/evdev.cpp

• xinput list

Dolphin provides a single XInput2//Virtual core pointer device as a single KeyboardMouse pointer.