HID: uhid: reintroduce uhid_hid_get_raw()

This reverts commit 4a76d370. Removing
it was a mistake, as we need a means to access GET_REPORT.

Reported-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>