Remove LED sync source and add keypress reporting
We return the modifiers as the valid bitmask so that the VirtualKeyboard can represent the correct keys as down. This is important when we have strokes like Left-Control + Right-Control + Keypad-1 (used in switching KVMs and such)
* Update hid_mouse_absolute.go
Added attribute to remove unnecessary out endpoint.
* Update hid_mouse_relative.go
Added attribute to remove unnecessary out endpoint.
* Update hid_keyboard.go
Added attribute to explicitly keep currently needed out endpoint and to make listed attributes consistent across the keyboard and mouse devices.
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Co-authored-by: Aveline <352441+ym@users.noreply.github.com>