HID: uhid: rename uhid_raw_request to uhid_hid_raw_request

We use strict prefixed in uhid.c:
  uhid_char_*: implement char-dev callbacks
  uhid_dev_*: implement uhid device management and runtime
  uhid_hid_*: implement hid-dev callbacks

uhid_raw_request is an hid callback, so rename it to uhid_hid_raw_request.

While at it, move it closer to it's extracted helpers and keep the same
order as in "struct hid_driver".

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>