HID: hid-lenovo-go: Add Lenovo Legion Go Series HID Driver

HID: hid-lenovo-go: Add Lenovo Legion Go Series HID Driver

Adds initial framework for a new HID driver, hid-lenovo-go, along with
attributes that report the firmware and hardware version for each
component of the HID device, of which there are 4 parts: The MCU, the
transmission dongle, the left "handle" controller half, and the right
"handle" controller half. Each of these devices are provided an attribute
group to contain its device specific attributes. Additionally, the touchpad
device attributes are logically separated from the other components in
another attribute group.

This driver primarily provides access to the configurable settings of the
Lenovo Legion Go and Lenovo Legion Go 2 controllers running the latest
firmware. As previously noted, the Legion Go controllers recently had a
firmware update[1] which switched from the original "SepentiaUSB" protocol
to a brand new protocol for the Go 2, primarily to ensure backwards and
forwards compatibility between the Go and Go 2 devices. As part of that
update the PIDs for the controllers were changed, so there is no risk of
this driver attaching to controller firmware that it doesn't support.

--
v6:
  - Make attributes static.
  - Use NULL instead of 0 in mcu_propery_out when there is no data.
v5:
  - Make version attributes static, retrieve them using delayed work
    during probe.
  - Fix endianness of version strings and print as hex.
v3:
  - Add hid-lenovo.c and Mark Pearson to LENOVO HID DRIVERS entry in MAINTAINERS

Reviewed-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Signed-off-by: Derek J. Clark <derekjohn.clark@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>