HID: lenovo: add support for Lenovo ThinkPad Keyboard Pro unit

This dock is used with the Thinkpad Helix 2 but suffers from an error
in the report descriptor where an usage max is 65535.

Add a report fixup for it and make the keyboard working.

Tested-by: Jonathan Oppenheim <lejono@gmail.com>
Tested-by: John Reid <owlman.lists@gmail.com>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>