HID: add multi-input quirk for GamepadBlock

The GamepadBlock game controller adapter needs HID_QUIRK_MULTI_INPUT
to split it up into two input devices. Without this quirk the
adapter is falsely recognized as only one device and mixes up the
inputs of the two connected controllers.

Signed-off-by: Florian Mueller <contact@petrockblock.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>